Tripeptidyl peptidase inhibitors

ABSTRACT

The invention is relative to a compound of formula (I) and its use as an inhibitor of the CCK-inactivating peptidase tripeptidyl peptidase (TPP II). The invention concerns in particular the treatment of eating disorder, obesity, psychotic syndrome and associated psychiatric disorders. It concerns also the cosmetic use of a compound (I) in particular to aid slimming.

This applicaton is a 371 of PCT/EP98/08558 filed Dec. 23, 1998.

The present invention relates to inhibitors of a membrane tripeptidylpeptidase responsible for the inactivation of endogenous neuropeptidessuch as cholecystokinins (CCKs).

Cholecystokinins (CCKs) are a family of hormonal and neuronal peptideswhich exert pleiotropic biological effects in the gut and brain. Forexample, CCK-33, the sulphated tritriaconta-peptide is implicated in thecontrol of gall-bladder contraction, gastric emptying and intestinalmotility (Dockray, G. J., Gastrointestinal Endocrinology: Receptors andPost-receptors Mechanisms (ed. Thompson, J.) 321-332 (Academic, New York1990)).

In cerebral neurons, CCK immunoreactivity corresponds mainly to thesulphated carboxy-terminal octapeptide CCK-8 (Vanderhaegen, J. J.,Signeau, J. C. and Gepts, W., Nature, 257, 604-605, (1975); Dockray, G.J., Nature 264, 568-570 (1976)). CCK immunoreactivity and dopaminecoexist in mesolimbic neurons and may be implicated in psychoticdisorders, (Hökfelt, T. et al., Nature, 285, 476-479 (1980)).

The actions of CCK are mediated by CCK_(A) and CCK_(B) receptors. CCK isknown to have a physiological role in the control of food intake, whichis enhanced by CCK_(A) agonists (Smith, G. P. and Gibbs, J., Ann. N.Y.Acad. Sci., 713, 236-241 (1994)), and the control of anxiety, which isdecreased by CCK_(B) antagonists (Woodruff, G. and Hughes, J. A., Rev.Pharmac., 31, 469-501 (1991)).

Tripeptidyl peptidase II (TPP II) is a CCK inactivating peptidase. TPPII is found in neurons responding to cholecystokinin as well as innon-neuronal cells. TPP II is considered to be a neuropeptidaseresponsible for CCK-8 inactivation (Rose, C et al, Nature, 380, 403409,(1996)). TPP II has the following characteristics:

1) in two steps, it rapidly cleaves the neuropeptide CCK-8 intobiologically inactive fragments with a reasonably high degree ofspecificity;

2) it is expressed by CCK-responsive neurons; and

3) its inhibition allows neuronal CCK-8 to escape inactivation andresults in CCK-like effects such as satiation in rodents.

TPP II could be involved in CCK-8 inactivation in the gastrointestinaltract. Exogenous CCK reduces food intake and elicits other behaviouralconcomitants of satiation. Food intake is increased by systemicadministration of CCK_(A) receptor agonists (Smith, G. P. and Gibb, J.,Ann. N.Y. Acad. Sci., 713, 236-241, (1994)). Endogenous CCK-controllingfood intake seems to be of neuronal rather than hormonal origin and actsupon peripheral CCK_(A) receptors on vagal afferent fibres (Smith, G. P.et al., Am. J. Physiol., 249, R638-R641 (1985)). In addition TPPII,although displaying preference for CCK, is also able to hydrolyseseveral other peptides with a free N-terminal ammonium group.

Inhibitors of TPP II are useful tools in investigating the functions ofCCK neurons and may be useful drugs for the treatment of disorders suchas over-eating, problems with gastrointestinal motility and psychoticsyndromes.

The present invention relates to compounds which are useful ininhibiting TPP II, processes for producing these compounds,pharmaceutical compositions comprising these compounds and the use ofthe compounds to inhibit TPP II.

The present invention provides a compound of the following formula I:

wherein: each R¹ may be the same or different, and is chosen from

halogen; OH; C₁-C₆ alkyl, C₁-C₆ alkenyl or C₁-C₆ alkynyl, optionallysubstituted by at least one halogen, OH or mixtures thereof; X(C₁-C₆alkyl), wherein X is S, O or OCO, and the alkyl is optionallysubstituted by at least one halogen, OH or mixtures thereof; SO₂(C₁-C₆alkyl), optionally substituted by at least one halogen; or YSO₃H,YSO₂(C₁-C₆ alkyl), wherein Y is O or NH and the alkyl is optionallysubstituted by at least one halogen; a diradical —X¹—(C₁-C₂alkylene)—X¹— wherein X¹ is O or S; a benzene ring fused to the indolinering;

n is from 0 to 4;

R² is CH₂R⁴, wherein R⁴ is

C₁-C₆ alkyl substituted by at least one halogen, OH or mixtures thereof;(CH₂)_(p)Z(CH₂)_(q)CH₃, wherein Z is O or S, p is from 0 to 5 and q isfrom 0 to 5, provided that p+q is from 0 to 5;

C₂-C₆ unsaturated alkyl; or C₃-C₆ cycloalkyl; or R² is C₁-C₆ alkyl orO(C₁-C₆ alkyl), each optionally substituted by at least one halogen;

R³ is H; C₁-C₆ alkyl optionally substituted by at least one halogen;(CH₂)_(p)ZR⁵ wherein p is from 1 to 3, Z is O or S and R⁵ is H or C₁-C₃alkyl; benzyl;

or a pharmaceutically acceptable acid addition salt thereof;

The invention provides in particular a compound of the above formula Iwherein: each R¹ may be the same or different, and is chosen from

halogen; OH; C₁-C₆ alkyl, optionally substituted by at least onehalogen, OH or mixtures thereof; X(C₁-C₆ alkyl), wherein X is S, O orOCO, optionally substituted by at least one halogen, OH or mixturesthereof; SO₂(C₁-C₆ alkyl), optionally substituted by at least onehalogen; or YSO₃H, YSO₂(C₁-C₆ alkyl), wherein Y is O or NH optionallysubstituted by at least one halogen;

n is from 0 to 4;

R² is CH₂R⁴, wherein R⁴ is

C₁-C₆ alkyl substituted by at least one halogen, OH or mixtures thereof;(CH₂)_(p)Z(CH₂)_(q)CH₃, wherein Z is O, S, p is from 0 to 5 and q isfrom 0 to 5, provided that p+q is from 0 to 5; C₂-C₆ unsaturated alkyl;or C₃-C₆ cycloalkyl,

or R² is C₁-C₆ alkyl or O(C₁-C₆ alkyl), each optionally substituted byat least one halogen;

R³ is H or C₁-C₆ alkyl;

or a pharmaceutically acceptable acid addition salt thereof.

Compounds of formula (I) wherein n=0 or when n is not 0 wherein R¹ is ahalogen atom, a O(C₁-C₄)alkyl, OH or a (C₁-C₄)alkyl group, R² is CH₂R⁴with R⁴ being (CH₂)₂SCH₃, (CH₂)₂OH or cyclohexyl or R² is a (C₁-C₆)alkylgroup, and R³ is an hydrogen atom or a (C₁-C₄)alkyl group, are knownfrom WO 96/35805 and are not included in the present invention.

According to one aspect of the present invention, it is relative tocompounds of formula (I) wherein R² is CH₂R⁴, R⁴ being C₁-C₆ alkylsubstituted by at least one halogen; (CH₂)_(p)Z(CH₂)_(q)CH₃ wherein Z isO (p and q are as defined above); C₂-C₆ unsaturated alkyl; or R² isO(C₁-C₆)alkyl optionally substituted by at least one halogen.

According to another aspect of the present invention, it is relative tocompounds of formula (I) wherein n is not 0 and R¹ is C₁-C₆ alkylsubstituted by at least one halogen, OH or mixtures thereof; X(C₁-C₆alkyl) wherein X is S or OCO, optionally substituted by at least onehalogen, OH or mixtures thereof; O(C₁-C₆)alkyl substituted by at leastone halogen, OH or mixtures thereof; SO₂(C₁-C₆ alkyl), optionallysubstituted by at least one halogen; or YSO₃H, YSO₂(C₁-C₆ alkyl) whereinY is O or NH optionally substituted by at least one halogen.

According to another aspect, the present invention is directed tocompounds (I) wherein n is not 0 and R¹ represents a C₁-C₆ alkenyl orC₁-C₆ alkynyl group.

The alkyl groups may be straight-chain or branched. The alkyl groupshave from 1 to 6 carbon atoms, preferably from 1 to 4 carbon atoms.Suitable alkyl groups include methyl, ethyl, n-propyl, i-propyl,n-butyl, i-butyl or t-butyl. Preferred alkyl groups are C₁₋₄ straightchain alkyl. Typically a substituted alkyl group has from 1 to 6substituents and preferably from 1 to 3 substituents. Halogen istypically F,Cl,Br, or I, preferably Cl or F, most preferably F.

The alkenyl or alkynyl groups may be straight-chain or branched. Thesegroups contain from 1 to 6 carbon atoms, preferably from 1 to 4 carbonatoms.

Typical alkenyl groups include ethenyl.

Typical alkynyl groups include ethynyl.

Unsaturated alkyl groups (in R²) contain one or more double or triplebonds.

According to still another aspect of the invention, it is relative tocompounds (I) wherein R¹ is a diradical —X¹—(C₁-C₂ alkylene)—X¹— whereX¹ is as defined above. R¹ is typically —OCH₂O—.

The diradical is preferably attached to the indoline ring at thepositions 4 and 5 (4,5-positions) or at the positions 5 and 6(5,6-positions).

According to another aspect, the invention is directed to compounds (I)wherein R¹ represents a benzene ring fused to the indoline ring.

The benzene ring is preferably attached at the 4-positions, or at the5,6-positions.

The present invention provides also compounds (I) wherein R³ representsa C₁-C₆ alkyl substituted by at least one halogen; (CH₂)_(p)ZR⁵ where p,Z and R⁵ are as defined above, or a benzyl.

Preferably R³ is hydrogen, methyl or ethyl, and most preferably R³ isethyl.

Preferably R² is CH₂R⁴, wherein R⁴ is CF₃, CF₂CF₃, CH₂OCH₃, CH₂SCH₃,SCH₃, CH(OH)CH₃, CH₂F, CH₂Cl, C═CH₂, C═CH, or cyclopropyl, or R² isNHCH₃. More preferably R⁴ is CH₂OCH₃, CH(OH)CH₃, CH₂SCH₃, or R⁴ containsone or more halogen substituents, preferably the or each halogen isfluorine or chlorine, for example CH₂Cl, CH₂F, CHF₂, CF₃ or CF₂CF₃, andmost preferably R⁴ is CF₃.

Each R¹, which may be the same or different is preferably, CH₃, OCH₃,Cl, F, OH, OCF₃, OSO₃H, OSO₂CH₃, OCOCH₃, OSO₂CF₃, SO₂CH₃, SCH₃, NHSO₂CH₃or CF₃. Most preferably each R¹ is OCH₃, OH, Cl or F.

The number of substituents R¹ is 0, 1, 2, 3 or 4, and preferably, n is0, 1 or 2. When n is 1, R¹ is preferably at the 4-, 5- or 6-position,most preferably at the 4- or 5-position. When n is 2, the two R¹ groupsare preferably at the 4- and 5-positions, 4- and 6-positions or 5- and6-positions, and are most preferably at the 4- and 5-positions. When nis 3, the three R¹ groups are preferably at the 4-, 5- and 6-positions.

The compounds of the invention generally have at least two chiralcentres. These are the carbon atoms at the 2-position on the indolinering and the carbon atom to which R³ is attached. The stereochemistry ateach of the chiral centres may independently be (S) or (R). Preferablythe stereochemistry of at least one chiral centre is (S). Mostpreferably the stereochemistry at both chiral centres is (S). The(S),(S) stereochemistry corresponds to the stereochemistry of naturallyoccurring amino acids. However, it is not essential that thestereoisomers are separated. For example1-(2(S)-aminobutyryl)4-chloroindoline-2(R/S)-carboxylic acid(2,2,2-trifluoroethyl)amide trifluoroacetate and1-(2(S)-aminobutyryl)4-fluoroindoline-2(R/S)-carboxylic acid(2,2,2-trifluoroethyl)amide trifluoroacetate have been shown to haveuseful activity.

The invention also provides a method for inhibiting the activity of TPPII which comprises administering an effective amount of a compound offormula I or a pharmaceutically acceptable acid addition salt thereof toa mammalian subject.

In this respect, the invention provides a medicament acting as aninhibitor of the CCK-inactivating peptidase tripeptidyl peptidase(TPPII) and/or for the treatment of eating disorders, especially obesityand/or for the treatment of psychotic syndromes and associatedpsychiatric disorders, which comprises a therapeutically effectiveamount of a compound of formula I.

The invention also provides a compound of formula I or pharmaceuticalcompositions comprising a compound of formula I for use in the treatmentof the human or animal body, particularly for the treatment of eatingdisorders, especially obesity.

The invention further provides the use of a compound of formula I forthe manufacture of a medicament for inhibiting the activity of TPP IIand/or for treating eating disorders, especially obesity.

The compounds of the invention may be administered alone or togetherwith any other known compound for the treatment for obesity. Suitabletreatments include those known in the art, for example treatment with anadrenergic β₃-receptor agonist, a histamine H₃-receptor antagonist, aneuropeptide Y receptor (NPY-5)antagonist, a compound acting on theamylin receptor or a compound that increases the levels ofnoradrenaline, dopamine or serotonin in the brain e.g. dexfenfluramine,sibutramine or fluoxetine. The compound of formula I and the otherobesity treatment compound may be provided in a form for simultaneous,separate or sequential administration.

The invention also provides a compounds of formula I or a pharmaceuticalcomposition comprising a compound of formula I for the treatment ofpsychotic syndromes and associated psychiatric disorders.

The invention also provides the cosmetic use of compound of formula I toaid slimming.

In this respect, the invention provides a cosmetic compositioncomprising a compound of formula I together with a physiologicallyacceptable carrier or diluent.

It is provided also a non-therapeutic method of treatment of the humanbody for slimming, comprising administering an effective amount of acompound of formula I optionally with a physiologically acceptablecarrier or diluent.

The compounds of formula I may be prepared by the following generalprocedure:

R¹, R², R³ are as defined above and R¹⁰ is H or a protecting group (e.g.benzyloxycarbonyl or t-butyloxycarbonyl).

a. Indole (or appropriately substituted indole)-2-carboxylic acid alkylester is reduced to the indoline ester (II) by magnesium turnings inmethanol, and this is coupled with a suitably protected amino acid (III)in the presence of a coupling reagent, such asbis(2-oxo-3-oxazolidinyl)phosphinic chloride (BOPCI) or a carbodiimidesuch as diisopropylcarbodiimide (DIC), dicyclohexylcarbodiimide (DCC) or1-(3-dimethylaminopropyl)-3-ethylcarbodiimide methiodide to form IV,where R¹ is OMe.

b. The acid of formula IV, where R¹ is OH, may then be prepared byhydrolyzing the corresponding ester of formula IV wherein R¹ is OMe withsodium hydroxide or lithium hydroxide in methanol-water solution at roomtemperature.

C. The diamides of formula IV, wherein R¹ is NHR², are formed bycoupling the acid of formula IV, where R¹ is OH, with an amine, R²NH₂,or a salt thereof in the presence of a coupling reagent, such as BOPCl,DIC, DCC etc.; or by reacting the ester of formula IV wherein R¹ is OMewith excess amine, e.g. MeOCH₂CH₂NH₂, MeSCH₂CH₂NH₂, MeCH(OH)CH₂NH₂ etc.,at a temperature between 15 and 60° C.

d. Removal of the protecting group R¹⁰ from the compound of formula IVwhere R¹ is NHR² to give compound I can be effected by hydrogenationwhen R¹⁰ is benzyloxycarbonyl over a catalyst such as palladium onactivated carbon; or by trifluoroacetic acid when R¹⁰ istert-butoxycarbonyl in dichloromethane.

e. An alternative route to obtain the diamides of formula IV wherein R¹is NHR², is to prepare an indoline 2-substituted carboxamide of formulaV, then couple it with the amino acid of formula III to obtain acompound of formula IV wherein R¹ is NHR². Removal of the protectinggroup R¹⁰ can be effected as described above. The compound of formula Vcan be prepared by reacting the indoline ester II with excess amine withor without methanol (when the amine is reactive), at a temperaturebetween 15 and 60° C., or by hydrolyzing the protected indoline ester toits acid, then treating the acid with an amine in the presence of acoupling reagent (such as BOPCl, DIC or DCC), followed by the removal ofthe protecting group, R¹⁰ as described above.

wherein R¹, R², R³ and R¹⁰ are as defined above.

The products obtained by these procedures can be converted into a salt.

Physiologically acceptable salts according to the invention which may beconveniently used include physiologically acceptable acid additionsalts, including the hydrochloride, acetate, trifluoroacetate andoxalate.

Acid addition salts according to the invention include mono- anddi-carboxylic acids in which the non-carbonyl moiety of the carboxylategrouping is selected from straight or branched chain alkyl (e.g. methyl,n-propyl, n-butyl or t-butyl); cyclic alkyl (e.g. cyclohexyl);alkoxyalkyl (e.g. methoxymethyl), carboxyalkyl (e.g. carboxyethyl),aralkyl (e.g. benzyl), aryloxyalkyl (e.g. phenoxymethyl), aryl (e.g.phenyl optionally substituted by halogen, C₁₋₄ alkyl or C₁₋₄ alkoxy oramino); sulfonic acids such as alkyl- or aralkyl-sulfonate (e.g.methanesulfonate); mono- or di-phosphoric acids which may or may not beblocked, amino acids (e.g. L-valine or L-isoleucine) and nitrate. Withregards to these acid components, unless otherwise specified, any alkylmoieties present in such acids preferably contain from 1 to 18 carbonatoms, particularly from 1 to 4 carbon atoms, in the case of straightchain alkyl groups, or 3 to 7 carbon atoms in the case of branched orcyclic alkyl groups. Any aryl moiety present in such acidsadvantageously comprises a phenyl group.

Any reference herein to any of the above compounds of the invention alsoincludes a reference to the physiologically acceptable salts thereof.

Particular compounds of formula I include:

1-(2(S)-aminobutyryl)-5-chloroindoline-2(S)-carboxylic acid(2,2,2-trifluoroethyl)amide;

1-(2(S)-aminobutyryl)-5-chloroindoline-2(S)-carboxylic acid2-chloroethylamide;

1-(2(S)-aminobutyryl)-indoline-2(S)-carboxylic acid(2-methylthioethyl)amide;

1-(2(S)-aminobutyryl)-indoline-2(S)-carboxylic acidN-(cyciopropylmethyl)amide;

1-(2(S)-aminobutyryl)-indoline-2(S)-carboxylic acid(2,2,2-trifluoroethyl)amide;

1-(2(S)-aminobutyryl)-5-hydroxyindoline-2(R/S)-carboxylic acid(2,2,2,-trifluoroethyl)amide;

1-(2(S)-aminobutyryl)4-chloroindoline-2(R/S)-carboxylic acid(2,2,2-trifluoroethyl)amide;

1-(2(S)-aminobutyryl)4-fluoroindoline-2(R/S)-carboxylic acid(2,2,2-trifluoroethyl)amide;

1-(2(S)-aminobutyryl)-5-methoxyindoline-2(R/S)-carboxylic acid(2,2,2-trifluoroethyl)amide;

1-(2(S)-aminobutyryl)-5-trifluoromethoxyindoline-2(R/S)-carboxylic acid(2,2,2-trifluoroethyl)amide;

and pharmaceutically acceptable salts thereof.

Particular compounds of formula I include also:

1-[2-(S)-aminobutyryl]-4,5-dichloro-indoline-2-(R/S)-carboxylic acidbutyl amide

1-[2-(S)-aminobutyryl]-4,5-dichloro-indoline-2-(S)-carboxylic acid2,2,2-trifluoroethylamide

1-[2-(S)-aminobutyryl]-5,6-dichloro-indoline-2-(S)-carboxylic acid2,2,2-trifluoroethylamide

1-[2-(S)-aminobutyryl]-benz-[e]-indoline-2-(S)-carboxylic acid2,2,2-trifluoroethylamide

1-[2-(S)-aminobutyryl]-5-O-sulfato-indoline-2(R/S)-carboxylic acid butylamide

1-[2-(S)-aminobutyryl]-benz-[e]-indoline-2-(S)-carboxylic acid butylamide

1-[2-(S)-aminobutyryl]-4,5-dichloro-indoline-2-(R/S)-carboxylic acid2,2,2-trifluoroethylamide

1-[2-(S)-aminobutyryl]-5-O-sulfato-indoline-2(R/S)-carboxylic acidtrifluoroethylamide

1-[2-(S)-aminobutyryl]-benz[f]-indoline-2-(S/R)-carboxylic acid2,2,2-trifluoroethylamide

1-[2-(S)-phenylalanyl)-5-Chloro-indoline-2(R/S)-carboxylic acid2,2,2-trifluoroethylamide

1-[2(S)-aminobutyryl]-4-methoxyindoline-2(S)-carboxylic acid(2,2,2-trifluoroethyl)amide

1-[2-glycyl]-5-chloroindoline-2(R/S)-carboxylic acid(2,2,2-trifluoroethyl)amide

1-[2(S)-alanyl]-5-chloroindoline-2(R/S)-carboxylic acid(2,2,2-trifluoroethylamide

1-[2(S)-norvalyl]-5-chloroindoline-2(R/S)-carboxylic acid(2,2,2-trifluoroethyl)amide

5 1-[2(S)-methionyl]-5-chloroindoline-2(R/S)-carboxylic acid(2,2,2-trifluoroethyl)amide

1-[2(S)-aminobutyryl]-4-methylindoline-2(R/S)-carboxylic acid(2,2,2-trifluoroethyl)amide

1-[2(S)-aminobutyryl]-4,5-dimethoxyindoline-2(R/S)-carboxylic acid(2,2,2-trifluoroethyl)amide

1-[2(S)-aminobutyryl]-4,5-methylenedioxyindoline-2(R/S)-carboxylic acid(2,2,2-trifluoroethyl)amide

1-[2(S)-aminobutyryl]-5-ethynylindoline-2(R/S)-carboxylic acid(2,2,2-trifluoroethyl)amide

and pharmaceutically acceptable salts thereof.

In addition to the above, compounds of formula I which, in vitro, have aKi value of less than 1.0 nM are especially preferred.

The compounds of formula I may be used in vitro or in vivo as TPP IIinhibitors. For in vivo use, the compounds may be useful in thedevelopment and standardisation of assays for TPP II and inhibitorsthereof.

For in vivo use the compounds may be useful in the control of stomachemptying and control of appetite for food.

The compounds of formula I may be administered to mammals includinghumans, by any route appropriate to the condition to be treated.Suitable routes include oral, rectal, nasal, topical (including buccaland sublingual), vaginal and parenteral (including subcutaneous,intramuscular, intravenous, intradermal, intrathecal and epidural). Itwill be appreciated that the preferred route may vary with, for example,the condition of the recipient.

For each of the above-identified utilities and indications, the amountrequired of the individual active ingredients will depend upon a numberof factors including the severity of the condition to be treated and theidentity of the recipient, and will also be at the discretion of theattendant physician. In general, however, for each of these utilitiesand indications, a suitable, effective dose will be in the range of from0.001 to 10 mg per kilogram body weight per day and most preferably inthe range of from 0.01 to 1 mg per kilogram body weight per day. Unlessotherwise indicated, all weights of active ingredient are calculated asthe parent compound, and for salts thereof the figures would beincreased proportionately.

The desired dose may suitably be presented as two, three, four or moresub-doses administered at appropriate intervals throughout the day.These sub-doses may be administered in unit dosage forms, for examplecontaining from 0.01 to 1000 mg, preferably from 0.01 to 500 mg ofactive ingredient per unit dosage form.

Doses of compounds of the invention may be administered at sub-daily ordaily intervals, or less frequently, for example on alternate days,weekly or fortnightly. In general the doses will be the same as theabove daily dose, although higher doses, particularly when formulated tobe released over a prolonged period of time, may be used.

While it is possible for the compounds to be administered alone it ispreferable to present them as pharmaceutical formulations. Theformulations of the present invention comprise at least one activeingredient, as above defined, together with one or more acceptablecarriers thereof and optionally other therapeutic ingredients. Thecarrier(s) must be “acceptable” in the sense of being compatible withthe other ingredients of the formulation and not deleterious to therecipients thereof.

The formulations include those suitable for oral, rectal, nasal, topical(including buccal and sublingual), vaginal or parenteral (includingsubcutaneous, intramuscular, intravenous, intradermal, intrathecal andepidural) administration. The formulations may conveniently be presentedin unit dosage form and may be prepared by any of the methods well knownin the art of pharmacy. Such methods include the step of bringing intoassociation the active ingredient with the carrier which constitutes oneor more accessory ingredients. In general the formulations are preparedby uniformly and intimately bringing into association the activeingredient with liquid carriers or finely divided solid carriers orboth, and then, if necessary, shaping the product.

Formulations of the present invention suitable for oral administrationmay be presented as discrete units such as capsules, cachets or tabletseach containing a predetermined amount of the active ingredient; as apowder or granules; as a solution or a suspension in an aqueous liquidor a non-aqueous liquid; or as an oil-in-water liquid emulsion or awater-in-oil liquid emulsion.

A tablet may be made by compression or moulding, optionally with one ormore accessory ingredients. Compressed tablets may be prepared bycompressing in a suitable machine the active ingredient in afree-flowing form such as a powder or granules, optionally mixed with abinder (e.g. povidone, gelatin, hydroxypropylmethyl cellulose),lubricant, inert diluent, preservative, disintegrant (e.g. sodium starchglycolate, cross-linked povidone, cross-linked sodium carboxymethylcellulose), surface-active or dispersing agent.

A capsule may be made by filling a loose or compressed powder on anappropriate filling machine, optionally with one or more additives.Examples of suitable additives include binders such as povidone;gelatin, lubricants, inert diluents and disintegrants as for tablets.

Compositions suitable for transdermal administration may be presented asdiscrete patches adapted to remain in intimate contact with theepidermis of the recipient for a prolonged period of time. Such patchessuitably contain the active compound 1) in an optionally buffered,aqueous solution or 2) dissolved in an adhesive or 3) dispersed in apolymer. A suitable concentration of the active compound is about 1% to35%, preferably about 3% to 15%.

Formulations suitable for parenteral administration include aqueous andnon-aqueous sterile injection solutions which may contain antioxidants,buffers, bacteriostats and solutes which render the formulation isotonicwith the blood of the intended recipient; and aqueous and non-aqueoussterile suspensions which may include suspending agents and thickeningagents, and liposomes or other microparticulate systems which aredesigned to target the compound to blood components or one or moreorgans. The formulations may be presented in unit-dose or multi-dosecontainers, for example sealed ampoules and vials, and may be stored ina freeze-dried (lyophilized) condition requiring only the addition ofthe sterile liquid carrier, for example water for injections,immediately prior to use.

The following Examples illustrate the invention.

The following abbreviations are used hereafter:

Abu: aminobutyryl; Ar: aromatic; Bn: benzyl; Boc: t-butoxycarbonyl; Ph:phenyl; t-Bu: t-butyl; s: singlet; d: doublet; t: triplet; m: multiplet;dd: double doublet; w: weak; vs: very small; str: strong.

EXAMPLE 1 Synthesis of1-(2(S)-aminobutyryl)-5-chloroindoline-2(S)-carboxylic acid(2,2,2-trifluoroethyl)amide trifluoroacetate5-Chloroindoline-2(R/S)-carboxylic acid methyl ester

5-Chloroindoline2-carboxylic acid ethyl ester (3 g, 13.4 mmol) andmagnesium turnings (0.652 g, 26.8 mmol) were suspended in dried methanol(300 ml). This mixture was stirred at 5 to 10° C. under nitrogen for 3hours, then poured into dichloromethane (400 ml), and washed withsaturated ammonium chloride solution, the organic layer was separated,and the aqueous layer was extracted with dichloromethane (3×100 ml). Thecombined organic layers were dried over sodium sulphate and evaporated.The resulting solid was chromatographed on silica gel usingdichloromethane as eluent, to furnish the indoline ester as a yellowsolid.

MS (EI) m/z 211 (M⁺, 100), 152 (M, 81). ¹HNMR (CDCl₃, 400 MHz) δ (ppm)6.70-7.05(m, 2H, ArH), 6.63 (d, 1H, ArH), 4.25-4.45 (m, 2H, NH and NCHCOof indoline), 3.77 (s, 3H, OCH₃), 3.29-3.42 (m, 2H, CH₂ of indoline).

1-(N-t-Butoxycarbonyl-2(S)-aminobutyryl)-5-chloroindoline-2(S)-carboxylicacid methyl ester

To a solution of 5-chloroindoline-2(R/S)-carboxylic acid methyl ester(1.2 g, 5.69 mmol) and N-t-butoxycarbonyl-2(S)-aminobutyric acid (1.27g, 6.25 mmol) dissolved in dried dichloromethane (10 ml) under nitrogenat 10° C., was added diisopropylcarbodiimide (0.98 ml, 6.30 mmol). Themixture was stirred at room temperature for 24 hours, then filtered. Thefiltrate was evaporated under vacuum to afford a brown solid which waspurified by column chromatography on silica gel using 20:1dichloromethane: diethyl ether as eluent. A white foam was obtainedwhich was the mixture of two diastereomers. The two diastereomers wereseparated by column chromatography on silica gel using 7:3 petroleumspirit:diethyl ether as eluent, and the pure (S,S) form was obtained asa white foam.

MS (Fab) m/z 397 (MH⁺, 8), 211 (49), 189(66), 145(100), 102 (56), 57(91). ¹HNMR (CDCl₃, 400 MHz) δ (ppm) 8.19 (d, 1H, ArH), 7.06-7.24 (m,2H, ArH), 5.23-5.42 (dd, 1H, NCHCO of indoline), 5.02 (d, 1H, NH ofAbu), 4.86-4.95, 4.33-4.39 (m, 1H, CH of Abu), 3.68, 3.69 (2s, 3H,OCH₃), 3.07-3.08, 3.30-3.62 (m, 2H, CNCHCO of indoline), 1.59-2.05 (m,2H, CH₂ of Abu), 1.44 (s, 9H, t-Bu), 1.09, 0.98 (2t, 3 H, CH₃ of Abu).

1-N-t-Butoxycarbonyl-2(S)-aminobutyryl)-6-chloroindoline-2(S)-carboxylicacid

To the solution of 1-(N-t-butoxycarbonyl-2(S)-aminobutyryl)-5-chloroindoline-2(S)-carboxylicacid methyl ester (1.2 g, 3 mmol) in methanol (20 ml), was added sodiumhydroxide(0.24 g, 6 mmol) in water (10 ml). The solution was stirred at5-10° C. for 4 hours. The mixture was poured into dichloromethane (50ml), and washed with cold potassium hydrogen sulphate (3×20 ml), thenwater (30 ml). The organic layer was dried over sodium sulphate, andevaporated to provide a white foam which was pure enough for the nextreaction.

MS (Fab) m/z 383(MH⁺, 8), 327(14), 197(12),145(63), 58(100). ¹HNMR(CDCl₃, 400 MHz) δ (ppm) 8.20 (d, 1H, ArH), 7.18-7.25 (m, 2H, ArH),5.66-6.50(m, 2H, NCHCO of indoline, COOH), 5.08-5.20 (dd, 1H, NH ofAbu), 4.70-4.80 (m, 1H, CH of Abu), 3.42-3.70 (m, 2H, CH₂ of indoline),1.50-2.00 (m, 2H, CH₂ of Abu), 1.57 (s, 9H, t-Bu), 1.05 (t, 3H, CH₃ ofAbu).

1-(N-t-Butoxycarbonyl-2(S)-aminobutyryl)-5-chloroindoline-2(S)-carboxylicacid (2,2,2-trifluoroethyl)amide

1-(N-t-Butoxycarbonyl-2(S)-aminobutyryl)-5-chloroindoline-2(S)-carboxylicacid (0.192 g, 0.5 mmol) and 2,2,2-trifluoroethylamine hydrochloride(0.205 g, 1.5 mmol) were dissolved in dried dichloromethane (5 ml) undernitrogen at 0° C., and triethylamine (0.63 ml, 4.5 mmol) was addedfollowed by bis(2-oxo-3-oxazolidinyl)phosphinic chloride (0.382 g, 1.5mmol). The temperature was allowed to rise to room temperature and themixture was stirred at room temperature for 24 hours, then filtered. Thefiltrate was concentrated under vacuum to give a brown solid which wascolumned on silica gel using 7:3 petroleum spirit: ethyl acetate aseluent to provide a white solid.

MS (Fab) m/z 464(MH⁺, 4), 408(8), 278(14), 152(24), 58(100). ¹HNMR(CDCl₃, 400 MHz) δ (ppm) 8.23-8.30 (m, 1H, CONH), 7.96-8.05(m, 1H, ArH),7.21-7.23(m, 2H, ArH), 4.83-5.17 (m, 2H, NCHCO of indoline and NH ofAbu), 3.41-4.09 (m, 5H, CH of Abu, CH₂ of indoline, CH₂CF₃), 0.85-1.98(m, 14H, CH₂of Abu, t-Bu, CH₃ of Abu).

1-2(S)-Aminobutyryl)-5-chloroindoline-2(S)-carboxylic acid(2,2,2-trifluoroethyl)amide trifluoroacetate

1-(N-t-Butoxycarbonyl-2(S)-aminobutyryl)-5-chloroindoline-2(S)-carboxylicacid (2,2,2-trifluoroethyl)amide (120 mg, 0.26 mmol) was dissolved indichloromethane (1 ml) in an ice-water bath, and trifluoroacetic acid (1ml) was added under nitrogen. The solution was stirred at 0 to 5° C.until gas evolution ceased. The solution was evaporated to dryness invacuo and the residue was treated with dried diethyl ether. A white foamwas obtained after drying.

m.p. 34-35° C. MS (Fab) m/z 364(MH⁺, 29), 58(100). ¹HNMR (DMSO-d₆, 400MHz) δ (ppm) 8.90-9.40, 8.85-8.92(m, 1H, CONH), 8.08-8.70, 7.10-7.50(m,6H, acidic H, ArH), 5.10-5.35 (m, 1H, NCHCO of indoline), 2.80-4.25 (m,5H, CH₂CF₃, CH of Abu, CH₂ of indoline), 1.75-2.00 (m, 2H, CH₂ of Abu),0.70-1.29(m, 5H, CH₃ of Abu, H₂O overlap). IR (KBr) cm⁻¹ 3430(broad, w)(N—H, O—H); 1687(vs), 1676(vs), 1632(w) (C═O); 1560(w), 1478(s) (C═C);1207(s), 1167(vs), 1126(s) (C—O, C—N, C—F). Elemental Analysis:calculated for C₁₅H₁₇ClF₃N₃O₂, 1.7CF₃COOH, C, 39.63, H, 3.38, N, 7.54%,found C, 39.45, H, 3.32, N, 7.43%.

EXAMPLE 2 Synthesis of1-2(S)-aminobutyryl)-5-chloroindoline-2(S)-carboxylic acid2-chloroethylamide trifluoroacetate1-(N-t-Butoxycarbonyl-2(S)-aminobutyryl)-S-chloroindoline-2(S)-carboxylicacid 2-chloroethylamide

Triethylamine (0.42 mL, 3 mmol) was added to the solution of1-(N-t-butoxycarbonyl-2(S)-aminobutyryl)-5-chloroindoline-2(S)carboxylicacid (0.152 g, 0.4 mmol) and 2-chloroethylamine hydrochloride (0.116 g,1 mmol) in dried dichloromethane (10 ml) under nitrogen at 0° C.,followed by bis(2-oxo-3-oxazolidinyl)phosphinic chloride (0.255 g, 1.0mmol). The temperature was allowed to rise to room temperature and themixture was stirred at room temperature for twenty-four hours, thenfiltered. The filtrate was concentrated under vacuum to give a brownsolid which was purified by column chromatography (silica gel, diethylether) to provide a white solid.

MS (FAB) m/z 445(MH⁺, 12), 444(33), 330(52), 258(46), 152(63), 57(100).¹HNMR (CDCl₃, 400 MHz) δ (ppm) 8.0-8.1 (m, 1H, CONH), 7.68-7.8 (m, 1H,ArH), 7.18-7.25 (m, 2H, ArH), 5.02-5.10 (m, 1H, H2 of indoline),4.80-4.90 (m, 1H, NH of Abu), 4.08-4.18 (m, 1H, CH of Abu), 3.40-3.75(m, 6H, H3 of indoline, CH₂CH₂Cl), 1.63-1.89 (m, 2H, CH₂ of Abu), 1.46(s, 9H, t-Bu), 0.95-1.23 (m, 3H, CH₃ of Abu).

1-(2(S)-Aminobutyryl)-5-chloroindoline-2(S)-carboxylic acid2-chloroethylamide trifluoroacetate

Trifluoroacetic acid (1 mL) was added dropwise to the solution of1-(N-t-butoxycarbonyl-2(S)-aminobutyryl)-5-chloroindoline-2(S)-carboxylicacid 2-chloroethylamide (100 mg, 0.225 mmol) in dichloromethane (1 mL)in an ice-water bath under nitrogen. This solution was stirred at 0-5°C. until gas evolution ceased, then evaporated to dryness under vacuumbelow 45° C., and the residue was treated with dried diethyl ether. Apink foam was obtained after drying.

m.p. 80-88° C. MS (FAB) m/z 348(M+4, 8), 347(M+3, 8), 346(M+2, 37),345(MH⁺, 13), 344(M, 60), 145(33), 57(100). ¹HNMR (DMSO-d₆, 400 MHz) δ(ppm) 8.70-8.92 (m, 1H, CONH), 8.20-8.50 (m, 3H, acidic H), 8.10 (d, 1H,J=8.5 Hz, ArH), 7.25-7.42 (m, 2H, ArH), 5.10 (dd, 1H, H2 of indoline),3.10-3.76 (m, 7H, CONCH₂CH₂Cl, CH of Abu, H3 of indoline), 1.75-2.00 (m,2H, CH₂ of Abu), 0.9-1.18 (m, 3H, CH₃ of Abu). IR (KBr disc) cm⁻¹3330(broad, w) (N—H, O—H); 1669(vs), 1676(vs) (C═O); 1536(w), 1478(s)(C═C); 1202(s), 1140(vs) (C—O, C—N, C—F). Elemental Analysis: calculatedfor C₁₅H₁₉Cl₂N₃O₂, 1.2CF₃COOH: C, 43.44; H, 4.23; N, 8.73%. Found: C,43.17; H, 4.52; N, 8.40%.

EXAMPLE 3 Synthesis of 1-(2(S)-aminobutyryl)-indoline-2(S) carboxylicacid (2-methylthioethyl)amide trifluoroacetate1-(N-t-Butoxycarbonyl-2(S)-aminobutyryl)-indoline-2(S)-carboxylicacid-(2-methylthioethyl)amide

To a solution of1-(N-t-butoxycarbonyl-2(S)-aminobutyryl)-indoline-2(S)-carboxylic acidmethyl ester (0.5 g, 1.4 mmol) in methanol (2 ml), was added2-methylthioethylamine (3 ml) under nitrogen, and the resulting solutionwas stirred at 60° C. for 48 hours. The solution was poured intodichloromethane (20 ml), and washed with 1M potassium hydrogen sulphate,the aqueous layer was extracted with dichloromethane (3×15 ml). Thecombined organic layers were dried over Na₂SO₄, and then the solvent wasevaporated. A white solid was obtained after column chromatography onsilica gel using diethyl ether as eluent.

MS (Fab) m/z 422 (MH⁺, 69), 322(52), 237(61), 118(100), 57(30). ¹HNMR(COdCl₃, 400 MHz) δ (ppm) 8.11-8.123 (m, 1H, ArH), 7.50-7.56 (m, 1H,CONH), 7.22-7.26 (m, 2H, ArH), 7.08-7.11 (m, 1H, ArH), 4.83-5.43 (m, 2H,NCHCO of indoline and NH of Abu), 4.13-4.21 (m, 1H, CH of Abu),3.36-3.56 (m, 4H, CONHCH ₂CH₂ of indoline), 2.59-2.60 (m, 2H, CH₂S),2.01 (s, 3H, SCH₃), 1.67-1.91 (m, 2H, CH ₂ of Abu), 1.45 (s, 9H, t-Bu),1.06-1.192 (t, 3H, CH₃ of Abu).

1-(2(S)-Aminobutyryl)-indoline-2(S)-carboxylic acid(2-methylthioethyl)amide trifluoroacetate

1-(N-t-Butoxycarbonyl-2(S)-aminobutyryl)-indoline-2(S)-carboxylic acid(2-methylthioethyl)amide (0.19 g, 0.45 mmol) was dissolved indichloromethane (1.5 ml) in an ice-water bath, and trifluoroacetic acid(1.5 ml) was added under nitrogen. The solution was stirred at 0 to 5°C. until gas evolution ceased. The solution was evaporated to dryness invacuo and the residue was treated with dried diethylether. A pink foamwas obtained after flash column chromatography on silica gel using 20:1dichloromethane: methanol as eluent.

m.p. 59.5-60.5° C.; MS (Fab) m/z 322 (MH⁺, 10), 155(35), 137(100). ¹HNMR(DMSO-d₆, 400 MHz) δ (ppm) 8.60 (m, 1H, CONH), 8.25-8.36(m, 2H, acidichydrogen), 8.14 (d, 1H, ArH), 7.22 -7.29, 7.08-7.12 (m, 3H, ArH),5.03-5.06 (m, 1H, NCHCO of indoline), 3.15-3.73 (m, 13H, CH of Abu, CH₂of indoline, CONHCH₂, overlap of H₂O), 2.53-2.73 (m, 2H, CH₂S), 2.06(s,3H, SCH₃), 1.79-2.00 (m, 2H, CH₂ of Abu), 0.99 (t, 3H, CH₃ of Abu). IR(KBr) cm⁻¹ 3449(m), 3073 (w) (N—H, O—H); 1673(s), 1649(s) (C═O); 1596(w), 1485 (m) (C═C); 1203(s), 1179(s), 1132(s) (C—O, C—N, C—F).Elemental Analysis: calculated for C₁₆H₂₃N₃O₂S, 1.2CF₃COOH, 0.5H₂O, C,47.30, H, 5.44, N, 8.99%, found C, 47.32, H, 5.35, N, 8.97%.

EXAMPLE 4 Synthesis of 1-(2(S)-aminobutyryl)-indoline-2(S)-carboxylicacid N-(cyclopropylmethyl)amide trifluoroacetate1-(N-t-Butoxycarbonyl-2(S)-aminobutyryl)-indoline-2(S)-carboxylic acidN-(cyclopropylmethyl)amide

In a like manner to example 1,1-(N-t-butoxycarbonyl-2(S)-aminobutyryl)-indoline-2(S)-carboxylic acid(0.30 g, 0.8 mmol) and cyclopropylmethylamine hydrochloride (0.26 g, 2.5mmol) were dissolved in dried dichloromethane (10 mL) under nitrogen at0° C., and triethylamine (1.03 mL, 7.4 mmol) was added followed bybis(2-oxo-3-oxazolidinyl)phosphinic chloride (0.63 g, 2.5 mmol). Thetemperature was allowed to rise to room temperature and the mixture wasstirred at room temperature for 24 hours, then poured intodichloromethane (25 mL) and washed (NaHCO₃). The organic was dried(Na₂SO₄) and evaporated to give an off white solid which was columned onsilica gel using 8:2 dichloromethane: ethyl acetate as eluent, and thenfurther purified by preparative hplc using 68% methanol.

MS(FAB) m/z 410 (MH⁺); ¹HNMR (DMSO 400 MHz): δ (ppm) 8.18-8.07 (m, 1H,NH of CONH), 7.34-7.01 (m, 4H, ArH), 5.47-4.78 (m, 1H, NCHCO ofindoline), 4.104.21 (m, 1H, CH of Abu), 3.62-3.41, 3.34-2.98 (m, 3H, CH₂of indoline & NH of CONH), 2.08-1.66 (m, >2H, CH₂ of Abu+H₂O), 1.52-1.34(s, 9H, t-Bu of Boc), 1.19-0.99 (m, 3H, CH₃of Abu), 0.52-0.33,0.221-0.09 (m, 5H, cyclopropane).

1-(2(S)-Aminobutyryl)-indoline-2(S)-carboxylic acid(N-cyclopropylmethyl)amide trifluoroacetate

1-(N-t-Butoxycarbonyl-2(S)-aminobutyryl)-indoline-2(S)-carboxylic acidN-(cyclopropylmethyl)amide (20 mg, 0.04 mmol) was dissolved indichloromethane (3 mL) in an ice-water bath, and trifluoroacetic acid(0.2 mL) was added under nitrogen. The solution was evaporated todryness under vacuum and the residue was treated with dried diethylether. A very hygroscopic pale yellow foam was obtained after drying.

m.p. 57-74° C.; MS(FAB) m/z 302 (MH⁺); ¹HNMR (DMSO 400 MHz): δ (ppm)8.09-8.17, 7.03-7.37 (m, 4H, ArH), 4.96-5.11 (m, 1H, NCHCO of indoline),3.55-3.78 (m, >10H, CH of Abu & CH of CONHCH₂+D₂O), 2.87-3.17 (m, 3H,CH₂ of indoline & NH of CONH & CH of CONHCH₂), 1.75-2.02 (m, 2H, CH₂ ofAbu), 0.88-1.15 (m, 3H, CH₃ of Abu), 0.36-0.49, 0.14-0.23 (m, 5H,cyclopropane). IR 3420(br, N—H, O—H, str overlapped by H₂O peak);1675(s, C═O str); 1464(m, aromatic C═C); 1204(s, C—N str); 1135(s, C—Ostr); Elemental Analysis: calculated for C₁₇H₂₃N₃O₂; 1.4(CF₃CO₂H): C,51.59; H, 5.33; N, 9.11%. Found: C, 51.66; H, 5.61; N, 8.90%.

EXAMPLE 5 Synthesis of 1-(2(S)-Aminobutyryl)-indoline-2(S)-carboxylicacid (2,2,2-trifluoroethyl)amide oxalate1-(N-Benzyloxycarbonyl-2(S)-aminobutyryl)-indoline-2(S)-carboxylic acid

To the solution of1-(N-benzyloxycarbonyl-2(S)-aminobutyryl)-indoline-2(S)-carboxylic acidmethyl ester (2.0 g, 5 mmol) in methanol (100 ml), was added lithiumhydroxide(0.233 g, 5.5 mmol) in water (5 ml). The solution was stirredat 5-10° C. for 5 hours. The mixture was poured into dichloromethane(100 ml), and washed with cold potassium hydrogen sulphate (3×50 ml),water (50 ml). The organic layer was dried over sodium sulphate, andevaporated to provide a white foam which was pure enough for the nextstep.

MS (Fab) m/z 383(MH⁺, 34), 254 (19), 163 (16), 118 (28), 91 (100). ¹HNMR(CDCl₃, 400 MHz) δ (ppm) 8.24-8.29, 7.07-7.35(m, 9H, ArH), 5.97-6.02,5.69-5.72, 4.70-5.31 (m, 6H, CH and NH of Abu, NCHCO of indoline, MS(Fab) m/z 330 (MH+, 100), 245(18), 118 (20), 95 (16), 58(52). ¹HNMR(DMSO-d₆, 400 MHz) δ (ppm) 9.42-9.43, 8.92-9.00(m, 1H, CONH), 4.50-10.00(acidic hydrogen overlap), 8.12-8.14 (m, 1H, ArH), 7.06-7.23 (m, 3H,ArH), 5.15-5.21, 4.60-4.69 (m, 1H, NCHCO of indoline), 3.62-4.01 (m, 5H,CH of Abu, CH₂ of indoline, CONHCH₂CF₃), 1.80-1.95 (m, 2H, CH₂ of Abu),0.92-1.03 (m, 3H, CH₃ of Abu). IR (KBr) cm⁻¹ 3450(w), 3330 (w), 3232(w),3069(w) (N—H, O—H), 1695(s), 1682(s), 1662 (s), 1651(s) (C═O), 1597(w),1559(w), 1483(s) (C═C), 1276 (s), 1161(s) (C—O, C—N, C—F). ElementalAnalysis: calculated for C₁₅H₈N₃O₂, (COOH)₂, 1.1H₂O, C, 46.49, H, 5.10,N, 9.57%, found C, 46.24, H, 5.04, N, 9.71%.

EXAMPLE 6 Synthesis of1-(2(S)-aminobutyryl)-5-hydroxyindoline-2(R/S)-carboxylic acid(2,2,2,-trifluoroethyl)amide trifluoroacetate5-Benzyloxyindoline-2(R/S)-carboxylic acid methylester

5-Benzyloxyindole-2-carboxylic acid ethylester (3 g, 10.1 mmol) andmagnesium turnings (1.2 g, 50 mmol) were suspended in dried methanol(180 mL). This mixture was stirred at 5-10° C. under nitrogen for 3hours, then poured into dichloromethane, and washed with saturatedammonium chloride solution. The organic layer was separated, and theaqueous layer was extracted with dichloromethane. The combined organiclayers were dried over sodium sulphate and evaporated to leave a brownsolid which was further purified by column chromatography (silica gel,dichloromethane) to afford a white solid.

¹HNMR (CDCl₃, 200 MHz) δ (ppm) 7.20-7.40 (m, 5H, ArH of Bn), 6.62-6.83(m, 3H, ArH of indoline), 4.974 (s, 2H, CH₂Ph), 4.366 (dd, 1H, J₁=6.04Hz, J₂=9.53 Hz, H2 of indoline), 3.749 (s, 3H, COOCH₃), 3.325 (m, 2H, H3of indoline).

1-(N-t-Butoxycarbonyl-2(S)-aminobutyryl)-5-benzyloxyindoline-2(R/S)-carboxylicacid methylester

CH₂Ph, COOH), 3.28-3.65(m, 2H, CH₂ of indoline), 1.66-2.06(m, 2H, CH₂ ofAbu), 1.00-1.25(m, 3H, CH₃of Abu).

1-(N-Benzyloxycarbonyl-2(S)-aminobutyryl)-indoline-2(S)-carboxylic acid(2,2,2-trifluoroethyl)amide

1-(N-Benzyloxycarbonyl-2(S)-aminobutyryl)-indoline-2(S)-carboxylic acid(0.382 g, 1 mmol) and 2,2,2-trifluoroethylamine hydrochloride (0.207 g,1.5 mmol) were dissolved in dried dichloromethane (10 ml), andtriethylamine (5.5 mmol) was added, followed bybis(2-oxo-3-oxazolidinyl)phosphinic chloride (0.508 g, 2.0 mmol) undernitrogen at 0° C. The temperature was allowed to rise to roomtemperature and the mixture was stirred at room temperature for 24hours, then filtered. The filtrate was concentrated under reducedpressure to give a brown solid which was purified by columnchromatography on silica gel using 7:3 petroleum spirit: ethyl acetateas eluent to afford a white solid.

m.p. 189.5-190.5° C. MS (Fab)m/z 464(MH⁺, 100), 463 (17), 335(55),244(29). ¹HNMR (CDCl₃, 400 MHz) δ (ppm) 8.09-8.18, 7.60-7.68 (m, 1H,CONH), 7.10-7.36 (m, 9H, ArH), 4.88-5.60 (m, 4H, NCHCO of indoline andNH of Abu, CH₂Ph), 3.22-4.16(m, 5H, CH of Abu, CH₂ of indoline,CONHCH₂), 1.60-2.07 (m, 2H, CH₂of Abu), 1.05-1.13 (m, 3H, CH₃ of Abu).

1-(2(S)-Aminobutyryl)-indoline-2(S)-carboxylic acid(2,2,2-trifluoroethyl)amide oxalate

10% Palladium on activated carbon (20 mg) was added to the solution of1-(N-benzyloxycarbonyl-2(S)-aminobutyryl)-indoline-2(S)-carboxylic acid(2,2,2-trifluoroethyl)amide (90 mg, 0.19 mmol) in methanol (10 ml), andthe mixture was hydrogenated at 40 psi for 2.5 hours. After the catalystwas removed by filtration through celite, oxalic acid (18 mg) was addedto the filtrate, and the solution was evaporated to dryness underreduced pressure at a bath temperature less than 50° C. The pure whitecrystalline product was obtained by recrystallization from dried diethylether-methanol (40:1).

m.p. 148.5-149.0° C.

1-(3,3-Dimethylaminopropyl)-3-ethylcarbodiimide methiodide (2.98 g, 11mmol) was added to a cold solution (0° C.) of5-benzyloxyindoline-2(R/S)-carboxylic acid methylester (2.83 g, 10 mmol)and N-t-butoxycarbonyl-2(S)-aminobutyric acid (0.203 g, 11 mmol) indichloromethane (20 mL) under nitrogen. The mixture was stirred at roomtemperature for 22 hours, then washed with 10% citric acid, water. Theorganic layer was separated, and aqueous layers were extracted withdichloromethane. The combined organic layers were dried andconcentrated, and purified by column chromatography (silica gel, 1:1petroleum spirit: diethyl ether), a white solid was obtained.

MS(FAB) m/z 510 (MH⁺, 15), 509 (M⁺, 26), 57 (100).

1-(N-t-Butoxycarbonyl-2(S)-aminobutyryl)-5-benzyloxyindoline-2(R/S)-carboxylicacid

To a solution of1-(N-t-butoxycarbonyl-2(S)-aminobutyryl)-5-benzyloxyindoline-2(R/S)-carboxylicacid methylester (2.75 g, 5.76 mmol) in methanol (20 mL), was added thewater solution of sodium hydroxide (0.46 g, 11.52 mmol) under nitrogenat 10-15° C. The solution was stirred at room temperature for fourteenhours, then poured into dichloromethane and washed with potassiumhydrogen sulphate solution, water. The organic layer was separated anddried over magnesium sulphate, solvent removal gave a yellow foam whichwas pure enough for the next step.

MS (FAB) m/z 477(MNa⁺, 77), 455 (MH⁺, 28), 399(40), 269(94), 178(91),57(100).

1-(N-t-Butoxycarbonyl-2(S)-aminobutyryl)-5-benzyloxyindoline-2(R/S)-carboxylicacid (2,2,2-trifluoro)ethylamide

Triethylamine (4.9 mL, 33 mmol) was added to the solution of1-(N-t-butoxycarbonyl-2(S)-aminobutyryl)-5-benzyloxyindoline-2(S)-carboxylicacid (2.6 g, 5.72 mmol) and 2,2,2-trifluoroethylamine hydrochloride(1.55 g, 11.4 mmol) in dried dichloromethane (50 mL) at 0° C. undernitrogen, followed by bis(2-oxo-3-oxazolidinyl)phosphinic chloride(2.902 g, 11.4 mmol). The temperature was allowed to rise to roomtemperature and the mixture was stirred at room temperature fortwenty-four hours, then filtered. The filtrate was concentrated undervacuum to give a brown solid which was purified by column chromatography(silica gel, 8:2 diethyl ether: petroleum spirit) to provide a whitesolid as the desired product.

MS (FAB) m/z 536(MH⁺, 26), 535(34), 350(64), 259(67), 91(89), 57(85).

1-(N-t-Butoxycarbonyl-2(S)-aminobutyryl)-5-hydroxyindoline-2(R/S)-carboxylicacid 2,2,2-trifluoroethylamide

A mixture of1-(N-t-butoxycarbonyl-2(S)-aminobutyryl)-5-benzyloxyindoline-2(R/S)-carboxylicacid 2,2,2-trifluoroethylamide (0.9 g, 1.68 mmol) and palladium onactivated carbon (0.1 g, 10% wet) in ethyl acetate (20 mL) washydrogenated under 30 psi hydrogen at room temperature overnight. Thenthe catalyst was removed by filtration over celite, and the filtrate wasevaporated to provide a white solid.

MS (FAB) m/z 468(MNa⁺, 23), 445 (MH⁺, 13), 346 (31), 260 (88), 134(100); ¹HNMR (CDCl₃, 300 MHz) δ (ppm) 8.30-8.35 (m, 1H, CONH), 7.50-7.90(m, 1H, ArH), 6.40-4.73 (m, 2H, ArH), 5.20-5.52 (m, 2H, OH, H2 ofindoline), 4.80-5.05 (m, 1H, NH of Abu), 3.70-4.20 (m, 3H, CH₂CF₃, CH ofAbu), 3.00-3.55 (m, 2H, H3 of indoline), 0.80-2.00 (m, 14H, CH₂ of Abu,t-Bu, CH₃ of Abu).

1-(2(S)-Aminobutyryl)-5-hydroxyindoline-2(R/S)-carboxylic acid(2,2,2-trifluoro)ethylamide trifluoroacetate

Trifluoroacetic acid (0.8 mL) was added dropwise to the solution of1-(N-t-butoxycarbonyl-2(S)-aminobutyryl)-5-hydroxyindoline-2(R/S)-carboxylicacid (2,2,2-trifluoro)ethylamide (200 mg, 0.44 mmol) in dichloromethane(1 mL) in an ice-water bath under nitrogen. This solution was stirred at0-5° C. until gas evolution ceased, then evaporated to dryness undervacuum below 45° C., and the residue was treated with dried diethylether to give a brown foam.

m.p. 76-88° C.; MS (FAB) m/z 691(2MH⁺, 7), 346 (MH⁺, 100), 261(31),154(27), 58(64); ¹HNMR (DMSO-d₆, 400 MHz) δ (ppm) 9.00-9.20, 8.7-8.85(m, 1H, CONH), 8.18-8.40 (m, 2H, acidic H), 7.92, 7.84 (d, 1H, J=9 Hz,ArH), 6.5-6.75 (m, 2H, ArH), 5.2-5.3, 5.0-5.1 (m, 1H, H2 of indoline),3.35-4.10 (m, 5H, CH₂CF₃, OH, CH of Abu, one H3 of indoline), 2.75-3.05(m, 1H, one H3 of indoline), 1.55-2.05(m, 2H, CH₂ of Abu), 1.01, 0.95,0.87 (3t, 3H, J=7.3 Hz, CH₃ of Abu). IR (KBr disc) cm⁻¹ 3291, 3090,2970(broad, m) (N—H, O—H); 1674(vs), 1675(vs) (C═O); 1620(w), 1490(m)(C═C); 1275(vs), 1160(s) (C—O, C—N, C—F). Elemental Analysis: calculatedfor C₁₅H₁₈F₃N₃O₃, 1.8CF₃COOH: C, 40.58; H, 3.62; N, 7.63%. Found: C,40.29; H, 3.70; N, 7.63%.

EXAMPLE 7 Synthesis of1-(2(S)-aminobutyryl)-4-chloroindoline-2(R/S)-carboxylic acid(2,2,2-trifluoroethyl)amide trifluoroacetate Methyl azidoacetate

A solution of methyl bromoacetate (150 g, 0.901 mol ) in dryacetonitrile (800 ml) was treated with sodium azide (58.57 g, 0.901 mol)under nitrogen and the mixture was heated for 20 hours at reflux. Aftercooling, water (150 ml) was added and the mixture was stirred for halfan hour. The top layer was separated and the bottom layer was treatedwith salt and extracted with diethyl ether. The organic phases werecombined and solvent removed in vacuum at a bath temperature notexceeding 50° C. to give a yellow oil which was used for the next stepwithout further purification.

¹HNMR (CDCl₃, 200 MHz) δ(ppm) 3.87(s, 2H, CH₂), 3.79 (s, 3H, OCH₃).

Methyl 2-azido-3-(2-chlorophenyl)propenoate

Sodium pieces(3.678 g, 160 mmol) were added in portions to methanol (200ml) over a 30 minute period. The resulting solution was cooled in a dryice/acetone bath to −18° C. and then over one hour a mixture of2-chlorobenzaldehyde (4.832 g, 40 mmol) and methyl azidoacetate (160mmol) was added at a rate that maintained the temperature below −15° C.After three hours, the solution was stored at 5° C. for two days to givecrystalline material which was collected by filtration and washed withcold hexane to give pure product as a yellow crystals.

¹HNMR(CDCl₃, 200 MHz), δ(ppm) 8.15-8.20 (m, 1H, ArCH═), 7.24-7.43 (m,4H, ArH), 3.93 (s, 3H, OCH₃).

4-Chloroindole-2-carboxylic acid methyl ester

Methyl 2-azido-3-(2-chlorophenyl)-propenoate (3.566 g, 144 mmol) wassuspended in toluene (800 ml) and the mixture was heated at reflux forthree hours, then cooled and allowed to stir at room temperatureovernight. A yellow crystalline material was obtained by filtration andrecrystallised from hexane.

MS (FAB) m/z 210(MH⁺, 43), 209 ((68), 139 (94), 77(100). ¹HNMR(CDCl₃,200 MHz) δ (ppm) 9.06-9.16(m, 1H, H—N), 7.18-7.40 (m, 4H, H—Ar), 3.98(s,3H, OCH₃).

4-Chloroindoline-2(R/S)-carboxylic acid methyl ester

4-Chloroindole-2-carboxylic acid methyl ester (0.8 g, 3.8 mmol) andmagnesium turnings (0.37 g, 15.2 mmol) were suspended in dried methanol(50 ml). This mixture was stirred at 5 to 10° C. under nitrogen for 3hours, then poured into dichloromethane (200 ml), and washed withsaturated ammonium chloride solution. The organic layer was separated,and the aqueous layer was extracted with dichloromethane (3×100 ml). Thecombined organic layers were dried over sodium sulphate and evaporated.A brown solid was obtained. After column chromatography on silica gelusing dichloromethane as eluent, a yellow oil was obtained.

MS (Fab) m/z 212 (MH⁺, 73), 211 (M, 84), 152(100). ¹HNMR (CDCl₃, 400MHz) δ (ppm) 6.99-7.05(m, 2H, ArH ), 6.58 (m, 1H, ArH), 4.53-4.62(m, 1H,NH of indoline), 4.424.46(m, 1H, NCHCO of indoline), 3.76 (s, 3H, OCH₃),3.31-3.42 (m, 2H, CH₂ of indoline).

1-(N-t-Butoxycarbonyl-2(S)-aminobutyryl)-4-chloroindoline-2(R/S)-carboxylicacid methyl ester

To a solution of 4-chloroindoline-2(R/S)-carboxylic acid methyl ester(0.41 g, 1.94 mmol) and N-t-butoxycarbonyl-2(S)-aminobutyric acid (0.47g, 2.33 mmol) dissolved in dried dichloromethane(10 ml) under nitrogenat 10° C., was added diisopropylcarbodiimide (0.36 ml, 2.33 mmol). Themixture was stirred at room temperature for 24 hours, then filtered. Thefiltrate was evaporated under vacuum to afford a brown solid which waspurified by column chromatography on silica gel using 20:1dichloromethane: diethyl ether as eluent. A white foam was obtainedwhich was the mixture of two diastereomers.

MS (Fab) m/z 397 (MH⁺, 15), 330(40), 189(95), 145(100); ¹HNMR (CDCl₃,400 MHz) δ (ppm) 8.06-8.17(dd, 1H, ArH), 7.04-7.27 (m, 2H, ArH),4.94-5.41 (m, 2H, NCHCO of indoline, NH of Abu), 4.27-4.59 (m, 1H, CH ofAbu), 3.79, 3.16 (2S, 3H, OCH₃), 0.87-2.0 (m, CH₂ of Abu, t-Bu, CH₃ ofAbu).

1-(N-t-Butoxycarbonyl-2(S)-aminobutyryl)-4-chloroindoline-2(R/S)-carboxylicacid

To the solution of1-(N-t-butoxycarbonyl-2(S)-aminobutyryl)4-chloroindoline-2(R/S)-carboxylicacid methyl ester (0.38 g, 0.96 mmol) in methanol (10 ml), was addedsodium hydroxide(0.046 g, 1.15 mmol) in water (4 ml). The solution wasstirred at 5 to 10° C. for 4 hours. The mixture was poured intodichloromethane (20 ml), and washed with cold potassium hydrogensulphate (3×20 ml), and water (20 ml). The organic layer was dried oversodium sulphate, and evaporated to provide a white foam which was pureenough for the next step.

MS (Fab) m/z 405(MNa⁺, 36), 330(35), 189(30), 145(100) 89(60); ¹HNMR(CDCl₃, 400 MHz) δ (ppm) 8.16 (2d, 1H, ArH), 7.06-7.27(m, 2H, ArH),4.80-6.20(m, COOH overlap), 5.68-5.70 (m, 1H, NCHCO of indoline),5.06-5.09 (m, 1H, NH of Abu), 4.664.86 (m, 1H, CH of Abu), 4.204.30,3.56-3.75 (m, 2H, CH₂ of indoline), 0.84-2.05(m, 14H, CH₂ of Abu, t-Bu,CH₃ of Abu).

1-(N-t-Butoxycarbonyl-2(S)-aminobutyryl)4-chloroindoline-2(R/S)-carboxylic acid (2,2,2-trifluoroethyl)amide

1-(N-t-Butoxycarbonyl-2(S)-aminobutyryl)-4-chloroindoline-2(S)-carboxylicacid (0.2 g, 0.52 mmol) and 2,2,2-trifluoroethylamine hydrochloride(0.142 g, 1.0 mmol) were dissolved in dried dichloromethane (10 ml)under nitrogen at 0° C., and triethylamine (0.44 ml, 3 mmol) was addedfollowed by bis(2-oxo-3-oxazolidinyl)phosphinic chloride (0.265 g, 1.0mmol). The temperature was allowed to rise to room temperature and themixture was stirred at room temperature for 24 hours, then filtered. Thefiltrate was concentrated under vacuum to give a brown solid which wascolumned on silica gel using 95:5 dichloromethane: diethyl ether aseluent to provide a white solid as the desired product.

MS (Fab) m/z486(MNa⁺, 25), 408(20), 364(30), 280(35), 152(100); ¹HNMR(CDCl₃, 400 MHz) δ (ppm) 7.92-8.30(m, 1H, CONH), 6.85-7.55(m, 3H, ArH),4.85-5.50 (m, 2H, NCHCO of indoline and NH of Abu), 3.18-4.15 (m, 5H, CHof Abu, CH₂ of indoline, CH₂CF₃), 1.44-2.00 (m, 2H, CH₂ of Abu), 1.44(s, 9H, t-Bu), 0.87-1.39 (m, 3H, CH₃ of Abu).

1-(2(S)-Aminobutyryl)-4-chloroindoline-2(R/S)-carboxylic acid(2,2,2-trifluoroethyl)amide trifluoroacetate

1-(N-t-Butoxycarbonyl-2(S)-aminobutyryl)4-chloroindoline-2(R/S)-carboxylicacid (2,2,2-trifluoroethyl)amide (70 mg, 0.15 mmol) was dissolved indichloromethane (1 ml) in an ice-water bath, and trifluoroacetic acid (1ml) was added under nitrogen. The solution was stirred at 0 to 5° C.until gas evolution ceased. The solution was evaporated to dryness invacuo and the residue was treated with dried diethyl ether. A white foamwas obtained after column chromatography on flash silica gel by using20:1 dichloromethane:methanol as eluent.

m.p. 104-106° C. MS (Fab) m/z 386(MNa⁺, 40), 364(MH⁺, 100), 152(60).¹HNMR (DMSO-d₆, 400 MHz) δ (ppm) 9.10-9.26 (m, 1H, CONH), 8.02-8.10 (m,1H, ArH), 7.08-7.40(m, 2H, ArH), 5.25-5.40 (m, 1H, NCHCO of indoline),2.96-4.10 (m, 5H, CH₂CF₃, CH of Abu, CH₂ of indoline, H₂O), 1.60-1.90(m,2H, CH₂ of Abu), 0.95, 0.84(2t, 3H, CH₃ of Abu). IR (KBr) cm⁻¹ 3370(broad, w) (N—H, O—H); 1730(vs), 1670 (vs), 1650(m) (C═O); 1590(s)1470(m), (C═C); 1205(s), 1162(vs), 1130(s) (C—O, C—N, C—F). ElementalAnalysis: calculated for C₁₅H₁₇ClF₃N₃O₂, 1.2CF₃COOH, 0.5H₂O C, 41.01, H,3.80, N, 8.25%, found C, 40.92, H, 3.81, N, 8.10%.

EXAMPLE 8 Synthesis of1-(2(S)-aminobutyryl)-4-fluoroindoline-2(R/S)-carboxylic acid(2,2,2-trifluoroethyl)amide trifluoroacetate 4-Fluoroindole-2-carboxylicacid

To a mixture of potassium ethoxide (5.317 g, 63 mmol) in diethyl ether(250 ml), ethyl oxalate (8.65 ml, 63 mmol) was added. After the solidethoxide disappeared, 2-fluoro-6-nitrotoluene (10 g, 63.18 mmol) indiethyl ether (20 ml) was added, and the mixture was stirred at 35 to38° C. for eighteen hours. Water (200 ml) was added, and the aqueouslayer separated from the ether layer. The deep red aqueous solution waswashed with ether (2×30 ml) to remove the unchanged starting materials,and acidified with a slight excess of hydrochloric acid, then theaqueous layer was extracted with ethyl acetate (3×100 ml). The combinedethyl acetate layers were evaporated and a brown solid was obtainedwhich gave a yellow solid after recrystallization from acetic acid. Thisyellow solid was dissolved in ammonia (70 ml, d=0.88 diluted to 100 mlwith water), then a hot solution of ferrous sulphate (90 g of hydratedcrystals in 100 ml of water) added, and the mixture was stirred on awater bath for an hour. After cooling, the black sludge of ferrichydroxide was filtered off and washed well with warm water containing alittle ammonia until a test portion gave only a faint milkiness onacidification. The filtration and washings were concentrated, thesolution acidified and extracted with ethyl acetate. The organic layerwas concentrated to give a brown solid as the desired product.

4-Fluoroindole-2-carboxylic acid methyl ester

25 4-Fluoroindole-2-carboxylic acid (0.65 g, 3.40 mmol) was dissolved inmethanol (50 ml), and 4-toluenesulfonic acid (1.4 g, 7.36 mmol) wasadded under nitrogen. The solution was stirred at reflux for 24 hours.Most of the methanol was removed by evaporation, and the residue wasdissolved in dicholoromethane (100 ml), washed with saturated sodiumcarbonate, and the organic layer was separated. The aqueous layer wasextracted with dichloromethane (3×50 ml). The combined organic layerswere washed with water, dried over sodium sulphate, and evaporated toyield a yellow crystalline material.

MS(EI) m/z 193(M⁺, 65), 161(100), 133(50), 107(35); ¹HNMR(CDCl₃,200MHz), δ (ppm) 8.90-9.10(m, 1H, NH of indole), 7.20-7.30 (m, 2H, ArH),6.76-6.85(m, 1H, ArH,), 3.95(s, 1H, OCH₃).

4-Fluoroindoline-2(R/S)-carboxylic acid methyl ester

4-Fluoroindole-2-carboxylic acid methyl ester (0.52 g, 2.7 mmol) andmagnesium turnings (0.136 g, 5.6 mmol) were suspended in dried methanol(30 ml). This mixture was stirred at 5 to 10° C. under nitrogen for 3hours, then poured into dichloromethane (100 ml), and washed withsaturated ammonium chloride solution. The organic layer was separated,and the aqueous layer was extracted with dichloromethane (3×40 ml). Thecombined organic layers were dried over sodium sulphate and evaporated.A brown solid was obtained. After column chromatography on silica gelusing dichloromethane as eluent, a reddish oil was obtained.

MS(EI) m/z 195(M⁺, 17), 172(20), 136(100), 109(40); ¹HNMR (CDCl₃, 200MHz) δ (ppm) 7.01-7.03(m, 1H, H-Ar), 6.42-6.50(m, 2H, ArH), 4.424.58 (m,2H, NH and NCHCO of indoline), 3.78 (s, 3H, OCH₃), 3.39-3.41 (m, 2H, CH₂of indoline).

1-(N-t-Butoxycarbonyl-2(S)-aminobutyryl)-4-fluoroindoline-2(R/S)-carboxylicacid methyl ester

To a solution of 4-fluoroindoline-2(R/S)-carboxylic acid methyl ester(0.43 g, 2.205 mmol) and N-t-butoxycarbonyl-2(S)-aminobutyric acid (0.47g, 2.33 mmol) dissolved in dried dichloromethane(10 ml) under nitrogenat 10° C., was added diisopropylcarbodiimide (0.36 ml, 2.33 mmol). Themixture was stirred at room temperature for 24 hours, then filtered. Thefiltrate was evaporated under vacuum to afford a brown solid which waspurified by column chromatography on silica gel using 10:1dichloromethane: diethyl ether as eluent. An off-white foam was obtainedwhich was the mixture of the two diastereomers.

MS (EI) m/z 381 (M⁺), 307(10), 195(80), 136(100), 57(96); ¹HNMR (CDCl₃,300 MHz) δ (ppm) 7.90-8.12(2d, 1H, ArH), 7.10-7.20 (m, 1H, ArH),6.70-7.00(m, 1H, ArH), 4.90-5.50 (m, 2H, NCHCO of indoline and NH ofAbu), 4.10-4.45 (m, 1H, CH of Abu), 3.80, 3.72 (2s, 3H, OCH₃),3.37-3.65, 3.10-3.25 (m, 2H, CH₂ of indoline), 1.50-1.95 (m, 2H, CH₂ ofAbu), 1.45 (s, 9H, t-Bu), 0.90-1.30 (m, 3H, CH₃ of Abu).

1-N-t-Butoxycarbonyl-2(S)-aminobutyryl)4-fluoroindoline-2(R/S)-carboxylicacid

To the solution of1-(N-t-butoxycarbonyl-2(S)-aminobutyryl)-4-fluoroindoline-2(R/S)-carboxylicacid methyl ester (0.27 g, 0.71 mmol) in methanol (10 ml), was addedsodium hydroxide (0.028 g, 0.71 mmol) in water (4 ml). The solution wasstirred at 5 to 10° C. for 4 hours. The mixture was poured intodichloromethane (20 ml), and washed with cold potassium hydrogensulphate (3×20 ml), and water (20 ml). The organic layer was dried oversodium sulphate, and evaporated to provide a white foam which was pureenough for the next reaction.

MS (Fab) m/z 389(MNa⁺, 100), 311(60), 182(55), 136(52), 136(52), 57(75);¹HNMR (CDCl₃, 400 MHz) δ (ppm) 7.92-8.05(m, 1H, ArH), 6.30-7.28 (m, 3H;ArH, COOH), 5.60-5.75(dd, 1H, NCHCO of indoline), 5.03-5.20 (m, 1H, NHof Abu), 4.624.74 (m, 1H, CH of Abu), 3.25-3.65 (m, 2H, CH₂ ofindoline), 0.85-2.05(m, 14H, CH₂ of Abu, t-Bu, CH₃ of Abu).

1-(N-t-Butoxycarbonyl-2(S)-aminobutyryl)-4-fluoroindoline-2(R/S)-carboxylicacid (2,2,2-trifluoroethyl)amide

1-(N-t-Butoxycarbonyl-2(S)-aminobutyryl)4-fluoroindoline-2(S)-carboxylicacid (0.12 g, 0.32 mmol) and 2,2,2-trifluoroethylamine hydrochloride(0.136 g, 1.0 mmol) were dissolved in dried dichloromethane (10 ml)under nitrogen at 0° C., and triethylamine (0.44 ml, 3 mmol) was addedfollowed by bis(2-oxo-3-oxazolidinyl)phosphinic chloride (0.265 g, 1.0mmol). The temperature was allowed to rise to room temperature and themixture was stirred at room temperature for 24 hours, then filtered. Thefiltrate was concentrated under vacuum to give a brown solid. A whitesolid was obtained by column chromatography on silica gel using 7:3petroleum spirit: ethyl acetate as eluent followed by recrystallizationfrom diethyl ether.

MS (Fab) m/z 448(MH⁺, 25), 392(30), 154(100), 137(59) ¹HNMR (CDCl₃, 400MHz) δ (ppm) 8.17-8.30(m, 1H, CONH), 7.65-7.95(m, 1H, ArH), 7.12-7.25,6.73-6.90(m, 2H, ArH), 4.80-5.40 (m, 2H, NCHCO of indoline and NH ofAbu), 3.15-4.20(m, 5H, CH of Abu, NCHCO of indoline, CH₂CF₃),0.86-2.00(m, 14H, CH₂of Abu, t-Bu, CH₃ of Abu).

1-(2(S)-Aminobutyryl)-4-fluoroindoline-2(R/S)-carboxylic acid(2,2,2-trifluoroethyl)amide trifluoroacetate

1-(N-t-Butoxycarbonyl-2(S)-aminobutyryl)4-fluoroindoline-2(R/S)-carboxylicacid (2,2,2-trifluoroethyl)amide (80 mg, 0.179 mmol) was dissolved indichloromethane (1 ml) in an ice-water bath, and trifluoroacetic acid(0.8 ml) was added under nitrogen. The solution was stirred at 0 to 5°C. until gas evolution ceased. The solution was evaporated to dryness invacuo and the residue was treated with dried ether. A white foam wasobtained after column chromatography on flash silica gel by using 20:1dichloromethane:methanol as eluent.

m.p. 57.5-58.5° C. MS (Fab) m/z 348 (MH⁺, 100), ¹HNMR (DMS0₆, 400 MHz) δ(ppm) 9.25-9.30 (m, 1H, CONH), 8.28-8.49 (m, 3H, acidic H), 7.97(d, 1H,ArH), 7.26-7.40, 6.93-7.05(m, 2H, ArH), 5.15-5.29 (dd, 1H, NCHCO ofindoline), 3.10-4.10 (m, 10H, CH₂CF₃, CH of Abu, CH₂ of indoline, H₂O),1.75-2.05(m, 2H, CH₂ of Abu), 1.03, 0.98 (2t, 3H, CH₃ of Abu). IR (KBr)cm⁻¹ 3443(broad, w), (N—H, O—H); 1686(vs), 1671 (vs) (C═O); 1601(w),1472(m) (C═C); 1208(vs), 1168(vs), 1143(s) (C—O, C—N, C—F). ElementalAnalysis: calculated for C₁₅H₁₇F₄N₃O₂, 2.5CF₃COOH, C, 37.99, H, 3.11, N,6.64%, found C, 38.14, H, 3.03, N, 6.39%.

EXAMPLE 9 Synthesis of1-(2(S)-aminobutyryl)-5-methoxyindoline-2(R/S)-carboxylic acid(2,2,2-trifluoroethyl)amide trifluoroacetate5-Methoxyindoline-2(R/S)-carboxylic acid methyl ester

5-Methoxyindole-2-carboxylic acid ethyl ester (2 g, 9.13 mmol) andmagnesium turnings (0.432 g, 18 mmol) were suspended in dried methanol(30 ml). This mixture was stirred at 5 to 10° C. under nitrogen for 3hours, then poured into dichloromethane (200 ml), and washed withsaturated ammonium chloride solution. The organic layer was separated,and the aqueous layer was extracted with dichloromethane (3×100 ml). Thecombined organic layers were dried over sodium sulphate and evaporated.A brown solid was obtained. After column chromatography on silica gelusing dichloromethane as eluent, a brown solid was obtained.

¹HNMR (CDCl₃, 400 MHz) δ (ppm) 6.62-6.72(m, 3H, ArH ), 4.23-4.39(m, 2H,NCHCO and NH of indoline), 3.76 (s, 3H, COOCH₃), 3.74 (s, 3H, ArOCH₃),3.29-3.42 (m, 2H, CH₂ of indoline).

1-(N-t-Butoxycarbonyl-2(S)-aminobutyryl)-5-methoxyindoline-2(R/S)-carboxylicacid methyl ester

To a solution of 5-methoxyindoline-2(R/S)-carboxylic acid methyl ester(1.5 g, 7.23 mmol) and N-t-butoxycarbonyl-2(S)-aminobutyric acid (1.62g, 7.96 mmol) dissolved in dried dichloromethane (15 ml) under nitrogenat 10° C., was added diisopropylcarbodiimide (1.00 ml, 7.96 mmol). Themixture was stirred at room temperature for 24 hours, then filtered. Thefiltrate was evaporated under vacuum to afford a brown solid which waspurified by column chromatography on silica gel using dichloromethane aseluent. A white foam was obtained which was the mixture of twodiastereomers.

MS (Fab) m/z 393 (MH⁺, 14), 207(76), 148(61), 57(100); ¹HNMR (CDCl₃, 400MHz) δ (ppm) 8.05-8.19 (2d, 1H, ArH), 6.70-6.76 (m, 2H, ArH),4.88-5.70(m, 2H, NCHCO of indoline, NH of Abu), 4.16-4.40 (m, 1H, CH ofAbu), 3.71-3.76(m, 6H, COOCH₃, ArOCH₃), 3.00-3.65 (m, 2H, CH₂ ofindoline), 1.55-2.05(m, 2H, CH₂ of Abu), 1.46, 1.42, 1.41 (3s, 9H,t-Bu), 1.08, 0.96, 0.90 (3t, 3H, CH₃ of Abu).

1-(N-t-Butoxycarbonyl-2(S)-aminobutyryl)-5-methoxyindoline-2(R/S)-carboxylicacid

To the solution of1-(N-t-butoxycarbonyl-2(S)-aminobutyryl)-5-methoxyindoline-2(R/S)-carboxylicacid methyl ester (1.3 g, 3.3 mmol) in methanol (20 ml), was addedsodium hydroxide(0.265 g, 6.6 mmol) in water (10 ml). The solution wasstirred at 5 to 10° C. for 4 hours. The mixture was poured intodichloromethane (40 ml), and washed with cold potassium hydrogensulphate (3×20 ml), and water (20 ml). The organic layer was dried oversodium sulphate, and evaporated to provide a white foam which was pureenough for the next step.

MS (Fab) m/z 379(MH+, 10), 323(16), 193(61), 145(70), 57(100); ¹HNMR(CDCl₃, 400 MHz) δ (ppm) 8.05-8.10 (m, 1H, ArH), 6.70-7.05 (m, 2H, ArH),4.90-5.75 (m, 2H, NCHCO of indoline, NH of Abu), 4.20-4.70 (m, 1H, CH ofAbu), 3.76 (s, 3H, ArOCH₃), 3.30-3.75 (m, 2H, CH₂ of indoline),0.80-2.05 (m, 14H, CH₂ of Abu, t-Bu, CH₃ of Abu).

1-(N-t-Butoxycarbonyl-2(S)-aminobutyryl)-5-methoxyindoline-2(R/S)-carboxylicacid (2,2,2-trifluoroethyl)amide

1-(N-t-Butoxycarbonyl-2(S)-aminobutyryl)-5-methoxy-indoline-2(S)-carboxylicacid (0.38 g, 1 mmol) and 2,2,2-trifluoroethylamine hydrochloride (0.271g, 2.0 mmol) were dissolved in dried dichloromethane (20 ml) undernitrogen at 0° C., and triethylamine (0.7 ml, 5 mmol) was added followedby bis(2-oxo-3-oxazolidinyl)phosphinic chloride (0.509 g, 2 mmol). Thetemperature was allowed to rise to room temperature and the mixture wasstirred at room temperature for 24 hours, then filtered. The filtratewas concentrated under vacuum to give a brown solid which was columnedon silica gel using 7:3 petroleum spirit:ethyl acetate as eluent toprovide a white solid as the desired product.

MS (Fab) m/z 460(MH⁺, 14), 360(14), 274(60), 148(100), 57(81); ¹HNMR(CDCl₃, 300 MHz) δ (ppm) 7.96-8.25(m, 1H, CONH), 7.42-7.65(m, 1H, ArH),6.55-7.00(m, 2H, ArH), 4.80-5.60(m, 4H, NCHCO of indoline, NH of Abu,CH₂CF₃), 3.85-4.10 (m, 1H, CH of Abu), 3.80(s, 3H, ArOCH₃), 3.20-370(m,2H, CH₂ of indoline), 0.84-2.00 (m, 14H, CH₂of Abu, t-Bu, CH₃ of Abu).Elemental analysis: calculated for C₂₁H₂₈F₃N₃O₅ C, 54.9, H, 6.14, N,9.15%, found C, 54.79, H, 6.38, N, 9.09%

1-(2(S)-Aminobutyryl)-5-methoxyindoline-2(R/S)-carboxylic acid(2,2,2-trifluoroethyl)amide trifluoroacetate

1-(N-t-Butoxycarbonyl-2(S)-aminobutyryl)-5-methoxyindoline-2(R/S)-carboxylicacid (2,2,2-trifluoroethyl)amide (0.2 mg, 0.435 mmol) was dissolved indichloromethane (2 ml) in an ice-water bath, and trifluoroacetic acid (1ml) was added under nitrogen. The solution was stirred at 0 to 5° C.until gas evolution ceased. The solution was evaporated to dryness invacuo and the residue was treated with dried diethyl ether. A purplefoam was obtained which was the mixture of two diastereomers (30:70).

m.p. 63.5-66° C.; MS (Fab) m/z 719(2MH⁺, 15), 360(MH⁺, 100), 275(50),148(45), 58(80); ¹HNMR (DMSO-d₆, 400 MHz) δ (ppm) 9.20-9.30 (m, 1H,CONH), 8.15-8.50 (m, 3H, acidic H), 7.92-8.10 (2d, 1H, ArH), 6.75-7.15(m, 2H, ArH), 5.00-5.30(dd, 1H, NCHCO of indoline), 3.40-4.10(m, 7H,CH₂CF₃, OCH₃, CH of Abu, one CH₂ of indoline), 2.86-3.15 (m, 1H, one CH₂of indoline), 1.50-2.00 (m, 2H, CH₂ of Abu), 0.70-1.23 (m, 3H, CH₃ ofAbu). IR (KBr) cm⁻¹ 3403 (broad, w)(N—H, O—H); 1670(vs), 1664(vs) (C═O);1616(w), 1491(m) (C═C); 1205(vs), 1167(vs), 1160(s) (C—O, C—N, C—F).Elemental Analysis: calculated for C₁₆H₂₀F₃N₃O₃, 1.4CF₃COOH, 0.6H₂O, C,342.62, H, 34.30, N, 7.93%, found C, 42.61, H, 4.30, N, 7.86%.

EXAMPLE 10 Synthesis of1-(2(S)-aminobutyryl)-5-trifluoromethoxyindoline-2(R/S)-carboxylic acid(2,2,2-trifluoroethyl)amide trifluoroacetate5-Trifluoromethoxyindoline-2(R/S)-carboxylic acid methyl ester

5-Trifluoromethoxyindole-2-carboxylic acid ethyl ester (2.25 g, 8.24mmol) and magnesium turnings (0.50 g, 21.7 mmol) were suspended in driedmethanol (60 ml). This mixture was stirred at 5 to 10° C. under nitrogenfor 3 hours, then poured into dichloromethane (200 ml), and washed withsaturated ammonium chloride solution. The organic layer was separated,and the aqueous layer was extracted with dichloromethane (3×100 ml). Thecombined organic layers were dried over sodium sulphate and evaporated.A brown solid was obtained. After column chromatography on silica gelusing dichloromethane as eluent, a brown solid was obtained.

MS (EI) m/z 261 (M⁺, 28), 231(46), 214(20), 202(100), 116(51); ¹HNMR(CDCl₃, 400 MHz) δ (ppm) 6.88-6.96(m, 2H, ArH), 6.65-6.68(m, 1H, ArH),4.40-4.50(m, 2H, NCHCO and NH of indoline), 3.78 (s, 3H, COOCH₃),3.29-3.42 (m, 2H, CH₂ of indoline).

1-(N-t-Butoxycarbonyl-2(S)-aminobutyryl)-5-trifluoromethoxyindoline-2(R/S)-carboxylicacid methyl ester

To a solution of 5-trifluoromethoxyindoline-2(R/S)-carboxylic acidmethyl ester (1.95 g, 7.47 mmol) andN-t-butoxycarbonyl-2(S)-aminobutyric acid (1.52 g, 7.47 mmol) dissolvedin dried dichloromethane (15 ml) under nitrogen at 10° C., was addeddiisopropylcarbodiimide (1.00 ml, 7.96 mmol). The mixture was stirred atroom temperature for 24 hours, then filtered. The filtrate wasevaporated under vacuum to afford a brown oil which was purified bycolumn chromatography on silica gel first by using 95:5 dichloromethane:diethyl ether as eluent, then another column on silica gel by using 7:3petroleum spirit: diethyl ether. A yellow foam was obtained which wasthe mixture of two diastereomers.

MS (Fab ) m/z 447 (MH⁺, 31), 391(80), 347(56), 261(100), 202(99); ¹HNMR(CDCl₃, 300 MHz) δ (ppm) 8.15-8.32 (2d, 1H, ArH), 7.05-7.15 (m, 2H ArH),5.25-5.45 (m, 1H, NCHCO of indoline), 4.90-5.10 (m, 1H, NH of Abu),4.15-4.45 (m, 1H, CH of Abu), 3.74, 3.80, 3.82 (3s, 3H, COOCH₃),3.30-3.70 (m, 2H, CH₂ of indoline), 1.65-2.05 (m, 2H, CH₂ of Abu), 1.46,1.42 (2s, 9H, t-Bu), 0.80-1.20 (m, 3H, CH₃ of Abu).

1-(N-t-Butoxycarbonyl-2(S)-aminobutyryl)-5-trifluoromethoxyindoline-2(R/S)-carboxylicacid

To the solution of1-(N-t-butoxycarbonyl-2(S)-aminobutyryl)-5-trifluoromethoxyindoline-2(R/S)-carboxylicacid methyl ester (1.0 g, 2.24 mmol) in methanol (15 ml), was addedsodium hydroxide (0.134 g, 3.36 mmol) in water (10 ml). The solution wasstirred at 5 to 10° C. for 4 hours. The mixture was poured intodichloromethane (40 ml), and washed with cold potassium hydrogensulphate (3×20 ml), and water (20 ml). The organic layer was dried oversodium sulphate, and evaporated to provide a white foam which was pureenough for the next step.

MS (Fab) m/z 455(MNa⁺, 100), 377(35), 248(30), 202(40), 57 (61); ¹HNMR(CDCl₃, 400 MHz) δ (ppm) 8.15-8.30 (2d, 1H, ArH), 7.00-7.70 (m, 3H,COOH, ArH), 5.70-5.76, 5.18-5.23 (m, 1H, NCHCO of indoline), 5.40-5.50,5.00-5.10 (m, 1H, NH of Abu), 4.65-4.75, 4.20-4.30 (m, 1H, CH of Abu),3.20-3.70 (m, 2H, CH₂ of indoline), 1.60-2.00 (m, 2H, CH₂ of Abu), 1.45,1.42, 1.37 (3s, 9H, t-Bu), 0.90-1.15 (m, 3H, CH₃ of Abu).

1-(N-t-Butoxycarbonyl-2(S)-aminobutyryl)-5-trifluoromethoxyindoline-2(R/S)-carboxylicacid (2,2,2-trifluoroethyl)amide

1-(N-t-Butoxycarbonyl-2(S)-aminobutyryl)-5-trifluoromethoxy-indoline-2(S)-carboxylicacid (0.432 g, 1 mmol) and 2,2,2-trifluoroethylamine hydrochloride(0.271 g, 2 mmol) were dissolved in dried dichloromethane (20 ml) undernitrogen at 0° C., and triethylamine (0.7 ml, 5 mmol) was added followedby bis(2-oxo-3-oxazolidinyl)phosphinic chloride (0.509 g, 2 mmol). Thetemperature was allowed to rise to room temperature and the mixture wasstirred at room temperature for 24 hours, then filtered. The filtratewas concentrated under vacuum to give a brown solid which was columnedon silica gel using 8:2 dichloromethane: diethyl ether as eluent toprovide an off-white solid as the desired product.

MS (Fab) m/z 514(MH⁺, 25), 458(35), 414(35), 328(65), 202(100), 57(85);¹HNMR (CDCl₃, 300 MHz) δ (ppm) 8.35-8.45 (m, 1H, CONH), 8.04-8.20,7.50-7.60 (m, 1H, ArH), 6.90-7.20 (m, 2H, ArH), 4.80-5.55 (m, 2H, NCHCOof indoline, NH of Abu), 3.204.20 (m, 5H, CH₂CF₃, CH of Abu, CH₂ ofindoline), 1.55-2.00 (m, 2H, CH₂ of Abu), 1.45 (s, 9H, t-Bu), 0.85-1.25(m, 3H, CH₃ of Abu). Elemental analysis: calculated for C₂₁H₂₅F₆N₃O₅ C,49.13, H, 4.91, N, 8.18%, found C, 49.20, H, 4.83, N, 8.11%

1-(2(S)-Aminobutyryl)-5-trifluoromethoxyindoline-2(R/S)-carboxylic acid(2,2,2-trifluoroethyl)amide trifluoroacetate

1-(N-t-Butoxycarbonyl-2(S)-aminobutyryl)-5-trifluoromethoxyindoline-2(R/S)-carboxylicacid (2,2,2-trifluoroethyl)amide (260 mg, 0.5 mmol) was dissolved indichloromethane (2 ml) in an ice-water bath, and trifluoroacetic acid(0.8 ml) was added under nitrogen. The solution was stirred at 0 to 5°C. until gas evolution ceased. The solution was evaporated to dryness invacuo and the residue was treated with dried diethyl ether. A brown foamwas obtained.

MS (Fab) m/z 827(2MH⁺, 5), 414 (MH⁺, 100), 328(10), 202(15), 58(50);¹HNMR (DMSO-d₆, 400 MHz) δ (ppm) 9.20-9.35 (2t, 1H, CONH), 8.30-8.50 (m,3H, acidic H), 8.19, 8.08 (d, 1H, ArH), 7.20-7.50 (m, 2H, ArH),5.39-5.42, 5.19-5.23(m, 1H, NCHCO of indoline), 3.50-4.10 (m, 4H,CH₂CF₃, CH of Abu, one CH₂ of indoline), 2.90-3.20 (m, 1H, one CH2 ofindoline), 1.70-2.05 (m, 2H, CH₂ of Abu), 1.04, 0.98, 0.90 (3t, 3H, CH₃of Abu). IR (KBr) cm⁻¹ 3463(broad, w) (N—H, O—H); 1688(vs), 1671(vs)(C═O); 1620(w), 1486(m) (C═C); 1268(vs), 1209(vs), 1171(s) (C—O, C—N,C—F). Elemental Analysis: calculated for C₁₆H₁₇F₆N₃O₃, 1.9CF₃COOH, C,37.75, H, 3.02, N, 6.67% , found C, 37.97, H, 3.09, N, 6.42%.

EXAMPLE 11 Synthesis of1-[2-(S)-aminobutyryl]-4,5-dichloro-indoline-2-(R/S)-carboxylic acidbutyl amide trifluoroacetate Ethyl 4,5-dichloroindole-2-carboxylate

3,4-Dichlorophenylhydrazine hydrochloride (25 g, 117 mmol) was treatedwith ethyl pyruvate (25.6 ml, 234 mmol) in ethanol (400 ml) and stirredovernight at room temperature. The reaction mixture was cooled to 0° C.and 200 ml of hexane was added. After filtration, 30 g of a light brownyellow precipitate was obtained, mp=108-113° C. This compound (10 g,36.3 mmol) was cyclised by refluxing for 4 h in toluene in the presenceof anhydrous p-toluenesulfonic acid (10 g, 58 mmol) obtaining 4.5 9(47%) of a mixture of ethyl 4,5-dichloroindole-2-carboxylate and ethyl5,6-dichloroindole-2-carboxylate which were separated by flash columnchromatography on silica gel using benzene as eluent. MP: 215-217° C.

4,5-Dichloroindoline-2-(R/S)-carboxylic acid methyl ester

This compound was prepared from ethyl 4, 5-dichloroindole-2-carboxylateas described in Example 1, using 6-7 eq. of magnesium turnings insteadof 2-3 eq. of magnesium turnings.

1-[N-t-Butoxycarbonyl-2-(S)-aminobutyryl]-4,5-dichloroindoline-2-(R/S)-carboxylicacid methyl ester

This compound was prepared from 4,5-dichloroindoline-2-(R/S)-carboxylicacid methyl ester as described in Example 1. The product can be used forthe next reaction with or without the separation of two diastereoisomersby column chromatography on silica gel.

1-[N-t-Butoxycarbonyl-2-(R/S)-aminobutyryl]-4,5-dichloroindoline-2-(R/S)-carboxylicacid

This compound was prepared from 4,5-dichloroindoline-2-(R/S)-carboxylicacid methyl ester as described in Example 1. The product can be used forthe next reaction with or without the separation of two diastereoisomersby column chromatography on silica gel.

1-[N-t-Butoxycarbonyl-2-(S)-aminobutyryl]-4,5-dichloroindoline-2-(R/S)-carboxylicacid butyl amide

This compound was prepared from1-(N-t-butoxycarbonyl-2-(S)-aminobutyryl)-4,5-dichloroindoline-2-(R/S)-carboxylicacid as described in Example 1, using butylamine instead oftrifluoroethylamine hydrochloride.

1-[2-(S)-Aminobutyryl]-4,5-dichloroindoline-2-(R/S)-carboxylic acidbutyl amide trifluoroacetate

This compound was prepared from1-(N-t-butoxycarbonyl-2-(S)-aminobutyryl)-4,5-dichloroindoline-2-(R/S)-carboxylicacid butyl amide as described in Example 1.

MP: 115-124° C.; Element analysis: C₁₇H₂₃Cl₂N₃O₂(CF₃COOH)1.9, Found: C,42.37%, H, 4.30%, N, 6.85%; Calculated: C, 42.21%, H, 4.26%, N, 6.93%.

EXAMPLE 12 Synthesis of1-[2-(S)-aminobutyryl]-4,5-dichloro-indoline-2-(S)-carboxylic acid2,2,2-trifluoroethylamide trifluoroacetate1-[N-t-Butoxycarbonyl-2-(S)-aminobutyryl-4,5-dichloroindoline-2-(S)-carboxylicacid methyl ester

This compound was prepared by the procedure described in Example 11. The(S)-isomer was separated by flash column chromatography on silica gelusing petroleum ether: ether (7:3) as eluent.

1-N-t-Butoxycarbonyl-2-(S)-aminobutyryl]-4,5-dichloroindoline-2-(S)-carboxylicacid

This compound was prepared from1-(N-t-Butoxycarbonyl-2-(S)-aminobutyryl)-4,5-dichloroindoline-2-(S)-carboxylicacid methyl ester as described in Example 1.

1-[N-t-Butoxycarbonyl-2-(S)-aminobutyryl]4,5-dichloroindoline-2-(S)-carboxylicacid 2,2,2-trifluoroethylamide

This compound was prepared from1-(N-t-butoxycarbonyl-2-(S)-aminobutyryl)-4,5-dichloroindoline-2-(S)-carboxylicacid as described in Example 1.

1-[2-(S)-Aminobutyryl]-4,5-dichloroindoline-2-(S)-carboxylic-acid-2,2,2-trifluoroethylamidetrifluoroacetate

This compound was prepared from the above compound as described inExample 1.

MP: 92-108° C.; Element analysis:C₁₅H₁₆C₁₂F₃N₃O₂(CF₃COOH)1.4(CH₃COCH₃)0.2; Found: C, 38.94%, H, 3.08%, N,7.32%; Calculated: C, 38.81%, H, 3.29%, N, 7.38%.

EXAMPLE 13 Synthesis of1-[2-(S)-aminobutyryl]-5,6-dichloro-indoline-2-(S)-carboxylic acid2,2,2-trifluoroethylamide trifluoroacetate Ethyl5,6-dichloroindole-2-carboxylate

This compound was prepared from 3,4-dichlorophenylhydrazinehydrochloride and ethyl-pyruvate using the procedure described inExample 11.

5,6-Dichloro indoline 2-carboxylic acid methyl ester

This compound was prepared from ethyl 5,6-dichloroindole-2-carboxylateas described in Example 11.

1-[N-Butoxycarbonyl-2-(S)-aminobutyryl]-5,6-dichloroindoline-2-(S)-carboxylicacid methyl ester

This compound was prepared from 5,6-dichloroindoline 2-carboxylic acidmethyl ester as described in Example 11.

1-[N-t-Butoxycarbonyl-2-(S)-aminobutyryl]-5,6-dichloroindoline-2-(S)-carboxylicacid

This compound was prepared from1-(N-t-butoxycarbonyl-2-(S)-aminobutyryl)-5,6-dichloroindoline-2-(S)-carboxylicacid methyl ester as described in Example 1.

1-[N-t-Butoxycarbonyl-2-(S)-aminobutyryl]-5,6-dichloroindoline-2-(S)-carboxylicacid 2,2,2-trifluoroethylamide

This compound was prepared from1-(N-t-butoxycarbonyl-2-(S)-aminobutyryl)-5,6-dichloroindoline-2-(S)-carboxylicacid as described in Example 1.

1-[2-(S)-Aminobutyryl]-5,6-dichloroindoline-2-(S)-carboxylic-acid-2,2,2-trifluoroethylamidetrifluoroacetate

This compound was prepared from the above compound as described inExample 1.

MP: 145-158° C.; Element analysis: C₁₅H₁₆C₁₂F₃N₃O₂(CF₃COOH)1.2, Found:C, 39.09%, H, 3.29%, N, 7.53%; Calculated: C, 39.06%, H, 3.24%, N,7.85%.

EXAMPLE 14 Synthesis of1-[2-(S)-aminobutyryl]-benz-[e]-indoline-2-(S)-carboxylic acid2,2,2-trifluoroethylamide trifluoroacetate Methyl 2-azido-3-(1-naphthyl)propionate

1-Naphthaldehyde (7 g, 44.87 mmol) and methyl azidoacetate (20.64 g,179.5 mmol) were dissolved in 210 ml of methanol and cooled to −20° C.Then sodium methoxide (9.66 g, 25% wt.) was added dropwise such that thetemperature was kept below −10° C. After stirring at −15° C. for 3hours, the reaction mixture was kept in refrigerator (4° C.) for 2 daysto give the yellow crystalline product which was collected by filtrationand washed with cooled hexane to afford pure product as a yellowcrystalline solid (8 g, 70%).

Methyl benz[e]indole-2-carboxylate

This compound was prepared from methyl 2-azido-3-(1-naphthyl)propionateas described in Example 7.

Methyl benz[e]indoline-2-carboxylate

This compound was prepared from methyl benz[e] indole-2-carboxylate asdescribed in Example 11.

1-[N-t-Butoxycarbonyl-2-(S)-aminobutyryl]-benz[e]-indoline-2-(S)-carboxylicacid methyl ester

This compound was prepared from methyl benz[e] indoline-2-carboxylate asdescribed in Example 1. The (S)-isomer was obtained by recrystallizationfrom a solvent mixture of dichloromethane, ether, hexane as well asmethanol.

1-[N-t-Butoxycarbonyl-2-(S)-aminobutyryl]-benz[e]-indoline-2-(S)-carboxylicacid

This compound was prepared from1-(N-t-butoxycarbonyl)-2-(S)-aminobutyryl)-benz[e]-indoline-2-(S)carboxylicacid methyl ester as described in Example 1.

1-[N-t-Butoxycarbonyl-2-(S)-aminobutyryl]-benz[e]-indoline-2-(S)-carboxylicacid 2,2,2-trifluoroethylamide

This compound was prepared was prepared from1-(N-t-butoxycarbonyl)-2-(S)-aminobutyryl)-benz[e]-indoline-2-(S)-carboxylicacid as described in Example 1.

Element analysis: C₂₄H₂₈F₃N₃O₄; Found: C, 60.24%, H, 5.79%, N, 8.64%;Calculated: C, 60.12%, H, 5.88%, N, 8.76%; HPLC purity: 99.6%.

1-[2-(S)-Aminobutyryl]-benz[e]-indoline-2-(S)-carboxylic-acid-2,2,2-trifluoroethylamidetrifluoroacetate

This compound was prepared from the above compound as described inExample 1

MP: 64-78° C., Element analysis: C₁₉H₂₀F₃N₃O₂(CF₃COOH)1.7(CH₃COCH₃)0.5,Found: C, 47.73%, H, 4.04%, N, 6.81%; Calculated: C, 47.66%, H, 4.13%,N, 6.98%

EXAMPLE 15 Synthesis of1-[2-(S)-aminobutyryl]-5-O-sulfato-indoline-2(R/S)-carboxylic acid butylamide trifluoroacetate1-[N-t-Butoxycarbonyl-2(S)-aminobutyryl]-5-benzyloxyindoline-2(R/S)-carboxylicacid butyl amide

This compound was prepared from1-(N-t-butoxycarbonyl-2(S)-aminobutyryl)-5-benzyloxyindoline-2-(R/S)-carboxylicacid and butyl amine as described in Example 6.

1-[N-t-Butoxycarbonyl-2(S)-aminobutyryl]-5-hydroxyindoline-2-(R/S)-carboxylicacid butyl amide

This compound was prepared from1-(N-t-butoxycarbonyl-2(S)-aminobutyryl)-5-benzyloxyindoline-2-(R/S)-carboxylicacid butyl amide as described in Example 6.

1-[N-t-Butoxycarbonyl-2(S)-aminobutyryl]-5-O-triethylammonium-sulfateindoline-2-(R/S)-carboxylic acid butyl amide

1-(N-t-Butoxycarbonyl-2(S)-aminobutyryl)-5-hydroxyindoline-2-(R/S)-carboxylicacid butyl amide (70 mg, 0.17 mmol) was dissolved in the minimum volumeof anhydrous pyridine (1.5 ml) required to effect complete solution. Tothis solution was added solid triethylamine-sulfur trioxide (152 mg,0.84 mmol). After stirring at 0° C. for 3 hours and room temperature for2 days, the pyridine was removed by vacuum and the remaining solid waspurified by preparative TLC using dichloromethane/methanol as eluent toafford 65 mg of the title product as a white crystalline solid.

MS[ESP](negative)=498 [M−NHEt₃](100%).

1-[2(S)-Aminobutyryl]-5-O-sulfato-indoline-2-(R/S)-carboxylic acid butylamide trifluoroacetate

This compound was prepared from the above compound as described inExample 1, using less excess trifluoroacetic acid and low reactiontemperature (−10 to −5° C.).

MP: 85-135° C.; Element analysis:C₁₇H₂₅N₃O₆S(CF₃COOH)0.4(H₂O)0.4(CH₃OH)0.5, Found: C, 47.25%, H, 6.31%,N, 9.10%; Calculated: C, 46.94%, H, 6.07%, N, 8.97%; HPLC purity: 99.3%(55.53%+43.8%)(R+S isomer); MS(FAB): 400[M+1](40%), 422[M+Na](16%).

EXAMPLE 16 Synthesis of1-[2-(S)-aminobutyryl]-benz-[e]-indoline-2-(S)-carboxylic acid butylamide trifluoroacetate1-[-N-t-Butoxycarbonyl]-2-(S)-aminobutyryl)-benz[e]-indoline-2-(S)-carboxylicacid butyl amide

Was prepared from1-(N-t-butoxycarbonyl)-2-(S)-aminobutyryl)-benz[e]-indoline-2-(S)-carboxylicacid and butylamine as described in Example 14 and deprotected to givethe title product as described in Example 1.

MP: 76-88° C. Element analysis: C₂₁H₂₇N₃O₂(CF₃COOH)1.5(CH₃COCH₃)0.5,Found: C, 55.32%, H, 5.46%, N, 7.56% Calculated: C, 55.33%, H, 5.74%, N,7.59%. MS(FAB): 354(M+1) 100%. HPLC purity: 98.97%.

EXAMPLE 17 Synthesis of1-[2-(S)-aminobutyryl]-4,5-dichloro-indoline-2-(R/S)-carboxylic acid2,2,2-trifluoroethylamide trifluoroacetate1-[N-t-Butoxycarbonyl-2-(S)-aminobutyryl]-4,5-dichloroindoline-2-(R/S)-carboxylicacid 2,2,2-trifluoroethylamide

This compound was prepared from1-(N-t-butoxycarbonyl-2-(S)-aminobutyryl)-4,5-dichloroindoline-2-(S/R)-carboxylicacid and butylamine as described in Example 1.

1-[2-(S)-Aminobutyryl]-4,5-dichloroindoline-2-(R/S)-carboxylic-acid-2,2,2-trifluoroethylamidetrifluoroacetate

This compound was prepared from the above compound as described inExample 1.

MP: 68-78° C.; Element analysis:C₁₅H₁₆Cl₂F₃N₃O₂(CF₃COOH)1.5(CH₃COCH₃)0.3; Found: C, 38.6%, H, 3.62%, N,7.22%; Calculated: C, 38.7%, H, 3.32%, N, 7.16%. MS(FAB): 398(M+),32.5%. HPLC: 98.33%.

EXAMPLE 18 Synthesis of1-[2-(S)-aminobutyryl]-5-O-sulfato-indoline-2(R/S)-carboxylic acidtrifluoroethylamide trifluoroacetate1-[N-t-Butoxycarbonyl-2(S)-aminobutyryl]-5-benzyloxyindoline-2-(R/S)-carboxylicacid trifluoroethylamide

This compound was prepared from1-(N-t-butoxycarbonyl-2(S)-aminobutyryl)-5-benzyloxyindoline-2-(R/S)-carboxylicacid and trifluoroethylamine as described in Example 15.

1-[N-t-Butoxycarbonyl-2(S)-aminobutyryl]-5-hydroxyindoline-2-(R/S)-carboxylicacid trifluoroethylamide

This compound was prepared from1-(N-t-butoxycarbonyl-2(S)-aminobutyryl)-5-benzyloxyindoline-2-(R/S)-carboxylicacid trifluoroethylamide as described in Example 15.

1-[N-t-Butoxycarbonyl-2(S)-aminobutyryl]-5-O-triethylammonium-sulfateindoline-2-(R/S)-carboxylic acid trifluoroethylamide

This compound was prepared from1-(N-t-butoxycarbonyl-2(S)-aminobutyryl)-5-hydroxyindoline-2-(R/S)-carboxylicacid trifluoroethylamide as described in Example 15.

MS(EPS-negative): 524(M-NEt₃H), 100%.

1-[2(S)-Aminobutyryl]-5-O-sulfato-indoline-2-(R/S)-carboxylic acidtrifluoroethylamide trifluoroacetate

This compound was prepared from the above compound as described inExample 15.

MP: 145-160° C.; Element analysis:C₁₅H₁₈F₃N₃O₆S(CF₃COOH)0.5(H₂O)0.5(CH₃OH)1.0, Found: C, 38.96%, H, 4.63%,N, 8.14%; Calculated: C, 39.01%, H, 4.53%, N, 8.03%; HPLC purity: 99.4%(68.35%+31.2%)(R+S isomer); MS(FAB): 426[M+1](100%).

EXAMPLE 19 Synthesis of1-[2-(S)-aminobutyryl]-benz[f]-indoline-2-(S/R)-carboxylic acid2,2,2-trifluoroethylamide trifluoroacetate hemi hydrate2-(Trichloroacetyl)pyrrole

This compound was prepared from pyrrole as described in literature (J.Org. Chem. 1993 58, 26, 7246).

Ethyl pyrrole-2-carboxylate

This compound was prepared from 2-(trichloroacetyl) pyrrole as describedin literature (J. Org. Chem. 1993, 58, 25, 7246).

2-[(5-Ethoxycarbonypyrrole-3-yl)carbonyl] benzoic acid

This compound was prepared from ethyl pyrrole-2-carboxylate as describedin literature (J. Chem. Soc. Perkin Trans I 1988, 3005).

2-[(5-Ethoxycarbonylpyrrol-3-yl)methyl] benzoic Acid

This compound was prepared from2-[(5-ethoxylcarbonylpyrrole-3-yl)carbonyl] benzoic acid as described inliterature (J. Chem. Soc. Perkin Trans I 1988, 3005).

Ethyl 4-{[(2-hydroxymethyl)phenyl]methyl}-1H-pyrrole-2-carboxylate

This compound was prepared from 2-[(5-ethoxycarbonylpyrrole-3-yl)methyl] benzoic acid as described in literature (J. Heterocyclic Chem.1993, 30, 217).

Ethyl 4-[(2-formylphenyl)methyl]-1H-pyrrole-2-carboxylate

This compound was prepared from Ethyl4-{[(2-Hydroxymethyl)phenyl]methyl}-1H-pyrrole-2-carboxylate asdescribed in literature (J. Heterocyclic Chem. 1993, 30, 217).

Ethyl benz[f]indole 2-carboxylate

This compound was prepared from ethyl4-[(2-formylphenyl)methyl]-1H-pyrrole-2-carboxylate as described inliterature (J. Heterocyclic Chem. 1993, 30, 217).

Methyl benz[f]indoline 2-carboxylate

This compound was prepared from ethyl benz[f]indole 2-carboxylate asdescribed in Example 1.

1-[N-t-Butoxycarbonyl-2-(S)-aminobutyryl]-benz[f]indoline2-(S)-carboxylic acid methyl ester

This compound was prepared from methyl benz[f] indoline 2-carboxylate asdescribed in Example 1. The (S)-isomer was separated by columnchromatography on silica gel.

1-[N-t-Butoxycarbonyl-2-(S)-aminobutyryl]-benz[f]indoline2-(S)-carboxylic acid

This compound was prepared from the above compound as described inExample 1.

1-[N-t-Butoxycarbonyl-2-(S)-aminobutyryl]-benz[f]indoline2-(S)-carboxylic acid 2,2,2-trifluoroethylamide

This compound was prepared from the above compound as described inExample 1.

1-[2-(S)-Aminobutyryl]-benz[f]indoline 2-(S)-carboxylic acid2,2,2-trifluoroethylamide trifluoroacetate hemi hydrate

This compound was prepared from the above compound as described inExample 1.

MP: 102-114° C. Element analysis:C₁₉H₂₀F₃N₃O₂(CF₃CO₂H)1.2(H₂O)0.5(Et₂O)0.1, Found: C, 49.34%, H, 4.19%,N, 7.54%, Calculated: C, 49.16%, H, 4.39%, N, 7.89%. HPLC purity: 98.9%MS(FAB): 380(M+1), 64.4%.

EXAMPLE 20 Synthesis of 1-[2-(S)-phenylalanyl)-5-Cl-indoline2(R/S)-carboxylic acid 2,2,2-trifluoroethylamide trifluoroacetate5-Chloro-indoline 2(R/S)-carboxylic acid methyl ester

This compound was prepared from ethyl 5-chloro indole carboxylate asdescribed in Example 1.

1-[N-tButoxycarbonyl-2(S) phenylalanyl]-5-Cl indoline 2(R/S) carboxylicacid methyl ester

This compound was prepared from 5-chloro-indoline 2(R/S)-carboxylic acidmethyl ester and N-t-Boc-phenyl alanine as described in Example 1.

1-[N -tButoxycarbonyl-2(S) phenylalanyl]-5-Cl indoline 2(R/S) carboxylicacid

This compound was prepared from 1-(N-t-butoxycarbonyl-2(S)phenylalanyl)-5-Cl indoline 2-(R/S) carboxylic acid methyl ester asdescribed in Example 1.

1-[N-tButoxycarbonyl-2(S) phenylalanyl]-5-Cl indoline 2(R/S) carboxylicacid 2,2,2 trifluoroamide.

This compound was prepared from 1-(N-t-butoxycarbonyl-2(S)phenylalanyl)-5-Cl indoline 2(R/S) carboxylic acid as described inExample 1.

1-[2-(S)-phenylalanyl]-5-Cl-indoline 2(R/S)-carboxylic acid2,2,2-trifluoroethylamide trifluoroacetate

This compound was prepared from the above compound as described inExample 1.

MP: 71-80° C. Element Analysis: C₂₀H₁₉ClF₃N₃O₂(CF₃CO₂H)1.7; Found: C,45,39%, H, 3.39%, N, 6.66%, Calculated: 45.36%, H, 3.37%, 6.78%.MS(FAB): 426(M+1), 79.8%. HPLC purity: 99.4%.

EXAMPLE 21 Synthesis of1-[2(S)-aminobutyryl]-4-methoxyindoline-2(S)-carboxylic acid(2,2,2-trifluoroethyl)amide trifluoroacetate4-Methoxyindoline-2(S)-carboxylic acid methyl ester

This compound was prepared from methyl 4-methoxyindole-2-carboxylate asdescribed in example 1.

1-[N-t-Butoxycarbonyl-2(S)-aminobutyryl]-4-methoxyindoline-2(S)-carboxylicacid methyl ester

This compound was prepared from 4-methoxyindoline-2(S)-carboxylic acidmethyl ester as described for in example 1. However this time thefiltrate was washed with water and the aqueous layer extracted withdiethyl ether (3×15 ml). The combined organic layers were dried overanhydrous sodium sulphate and concentrated under reduced pressure toafford a colourless oil which was purified by column chromatography onsilica gel using 20:1 dichloromethane:diethyl ether as eluent. A whitefoam was obtained after drying.

1-[N-t-Butoxycarbonyl-2(S)-aminobutyryl]-4-methoxyindoline-2(S)-carboxylicacid

This compound was prepared from1-[N-t-butoxycarbonyl-2(S)-aminobutyryl]-4-methoxyindoline-2(S)-carboxylicacid methyl ester as described in example 1.

1-[N-t-Butoxycarbonyl-2(S)-aminobutyryl]-4-methoxyindoline-2(S)-carboxylicacid (2,2,2-trifluoroethyl)amide

This compound was prepared from1-[N-t-butoxycarbonyl-2(S)-aminobutyryl]-4-methoxyindoline-2(S)-carboxylicacid as described in example 1.

1-[2(S)-Aminobutyryl]-4-methoxyindoline-2(S)-carboxylic acid(2,2,2-trifluoroethyl)amide trifluoroacetate

This compound was prepared from1-[N-t-butoxycarbonyl-2(S)-aminobutyryl]-4-methoxyindoline-2(S)-carboxylicacid (2,2,2-trifluoroethyl)amide as described in example 1.

mp 125-149° C.; Elemental analysis: C₁₆H₂₀F₃N₃O₃; 1.4(CF₃CO₂H); Found:C, 43.51%, H, 4.33%, N, 8.07%; Calculated: C, 43.51%, H, 4.16%, N,8.10%; HPLC purity: 97.5% (S isomer).

EXAMPLE 22 Synthesis of 1-[2-glycyl]-5-chloroindoline-2(R/S)-carboxylicacid (2,2,2-trifluoroethyl)amide trifluoroacetate5-Chloroindoline-2(R/S)-carboxylic acid methyl ester

This compound was prepared from ethyl 5-chloroindole-2-carboxylate asdescribed in example 1. However this time 5-6 equivalence of magnesiumturnings were used instead of 2-3 eq. of magnesium turnings.

1-[N-t-Butoxycarbonyl-2-glycyl]-5-chloroindoline-2(R/S)-carboxylic acidmethyl ester

This compound was prepared from 5-chloroindoline-2(R/S)-carboxylic acidmethyl ester and N-t-butoxycarbonylaminoacetic acid as described for inexample 21. The product was purified by column chromatography on silicagel using 7:3 petroleum spirit:diethyl ether as eluent.

1-[N-t-Butoxycarbonyl-2-glycyl]-5-chloroindoline-2(R/S)-carboxylic acid

This compound was prepared from1-[N-t-butoxycarbonyl-2-glycyl]-5-chloroindoline-2(R/S)-carboxylic acidmethyl ester as described in example 1.

1-[N-t-Butoxycarbonyl-2-glycyl]-5-chloroindoline-2(R/S)-carboxylic acid(2,2,2-trifluoroethyl)amide

This compound was prepared from1-[N-t-butoxycarbonyl-2-glycyl]-5-chloroindoline-2(R/S)-carboxylic acidas described for in example 21.

1-[2-glycyl]-5-chloroindoline-2(R/S)-carboxylic acid(2,2,2-trifluoroethyl)amide trifluoroacetate

This compound was prepared from1-[N-t-butoxycarbonyl-2-glycyl]-5-chloroindoline-2(R/S)-carboxylic acid(2,2,2-trifluoroethyl)amide as described in example 1.

mp 170-176° C.; Elemental analysis: C₁₃H₁₃ClF₃N₃O₂; 1.4(CF₃CO₂H); Found:C, 38.37%, H, 2.77%, N, 8.39%; Calculated: C, 38.31%, H, 2.93%, N,8.48%; HPLC purity: 98.2%.

EXAMPLE 23 Synthesis of1-[2(S)-alanyl]-5-chloroindoline-2(R/S)-carboxylic acid(2,2,2-trifluoroethyl)amide hemitrifluoroacetate5-Chloroindoline-2(R/S)-carboxylic acid methyl ester

This compound was prepared from ethyl 5-chloroindole-2-carboxylate asdescribed in example 22.

1-[N-t-Butoxycarbonyl-2(S)-alanyl]-5-chloroindoline-2(R/S)-carboxylicacid methyl ester

This compound was prepared from 5-chloroindoline-2(R/S)-carboxylic acidmethyl ester and N-t-butoxycarbonyl-L-alanine as described in example21.

1-[N-t-Butoxycarbonyl-2(S)-alanyl]-5-chloroindoline-2(R/S)-carboxylicacid

This compound was prepared from1-[N-t-butoxycarbonyl-2(S)-alanyl]-5-chloroindoline-2(R/S)-carboxylicacid methyl ester as described in example 1.

1-[N-t-Butoxycarbonyl-2(S)-alanyl]-5-chloroindoline-2(R/S)-carboxylicacid (2,2,2-trifluoroethyl)amide

This compound was prepared from1-[N-t-butoxycarbonyl-2(S)-alanyl]-5-chloroindoline-2(R/S)-carboxylicacid as described in example 21.

1-[²(S)-Alanyl]-5-chloroindoline-2(R/S)-carboxylic acid(2,2,2-trifluoroethyl)amide hemitrifluoroacetate

This compound was prepared from1-[N-t-butoxycarbonyl-2(S)-alanyl]-5-chloroindoline-2(R/S)-carboxylicacid (2,2,2-trifluoroethyl)amide as described in example 1.

mp 158-164° C.; Elemental analysis: C₁₄H₁₅ClF₃N₃O₂; 0.5(CF₃CO₂H); Found:C, 44.40%, H, 3.91%, N, 10.23%; Calculated: C, 44.29% H, 3.84% N,10.33%; HPLC purity: 99.7% (30.4%+69.3%) (R+S isomer).

EXAMPLE 24 Synthesis of1-[2(S)-norvalyl]-5-chloroindoline-2(R/S)-carboxylic acid(2,2,2-trifluoroethyl)amide trifluoroacetate1-[N-t-Butoxycarbonyl-2(S)-norvalyl]-5-chloroindoline-2(R/S)-carboxylicacid methyl ester

This compound was prepared from 5-chloroindoline-2(R/S)-carboxylic acidmethyl ester and N-t-butoxycarbonylaminopropionic acid as described inexample 21. The product was purified by column chromatography on silicagel using 8:2 petroleum spirit:diethyl ether as eluent.

1-[N-t-Butoxycarbonyl-2(S)-norvalyl]-5-chloroindoline-2(R/S)-carboxylicacid

This compound was prepared from1-[N-t-butoxycarbonyl-2(S)-norvalyl]-5-chloroindoline-2(R/S)-carboxylicacid methyl ester as described in example 1.

1-[N-t-Butoxycarbonyl-2(S)-norvalyl]-5-chloroindoline-2(R/S)-carboxylicacid (2,2,2-trifluoroethyl)amide

This compound was prepared from1-[N-t-butoxycarbonyl-2(S)-norvalyl]-5-chloroindoline-2(R/S)-carboxylicacid as described in example 21.

1-[2(S)-Norvalyl]-5-chloroindoline-2(R/S)-carboxylic acid(2,2,2-trifluoroethyl)amide trifluoroacetate

This compound was prepared from1-[N-t-butoxycarbonyl-2(S)-norvalyl]-5-chloroindoline-2(R/S)-carboxylicacid (2,2,2-trifluoroethyl)amide as described in example 1.

mp 130-138° C.; Elemental analysis: C₁₆H₁₉ClF₃N₃O₂; 1.4(CF₃CO₂H); Found:C, 42.07%, H, 3.63%, N, 8.02%; Calculated: C, 42.02%, H, 3.83% N, 7.82%.HPLC purity: 98.3% (R+S isomer)

EXAMPLE 25 Synthesis of1-[2(S)-methionyl]-5-chloroindoline-2(R/S)-carboxylic acid(2,2,2-trifluoroethyl)amide trifluoroacetate1-[N-t-Butoxycarbonyl-2(S)-methionyl]-5-chloroindoline-2(R/S)-carboxylicacid methyl ester

This compound was prepared from 5-chloroindoline-2(R/S)-carboxylic acidmethyl ester and N-t-butoxycarbonyl-L-methionine as described in example21. The product was purified by column chromatography on silica gelusing 3:1 petroleum spirit:ethyl acetate as eluent.

1-[N-t-Butoxycarbonyl-2(S)-methionyl]-5-chloroindoline-2(R/S)-carboxylicacid

This compound was prepared from1-[N-t-butoxycarbonyl-2(S)-methionyl]-5-chloroindoline-2(R/S)-carboxylicacid methyl ester as described in example 1. The product was purified bycolumn chromatography on silica gel using 5:1 dichloromethane:methanolas eluent.

1-[N-t-Butoxycarbonyl-2(S)-methionyl]-5-chloroindoline-2(R/S)-carboxylicacid (2,2,2-trifluoroethyl)amide

This compound was prepared from1-[N-t-butoxycarbonyl-2(S)-methionyl]-5-chloroindoline-2(R/S)-carboxylicacid as described for in example 21.

1-[2(S)-Methionyl]-5-chloroindoline-2(R/S)-carboxylic acid(2,2,2-trifluoroethyl)amide trifluoroacetate

This compound was prepared from1-[N-t-butoxycarbonyl-2(S)-methionyl]-5-chloroindoline-2(R/S)-carboxylicacid (2,2,2-trifluoroethyl)amide as described in example 1. The productwas purified by column chromatography on silica gel using 5:1dichloromethane: methanol as eluent.

mp 139-145° C.; Elemental analysis: C₁₆H₁₉ClF₃N₃O₂S; 0.1(CF₃CO₂H);Found: C, 46.41% H, 4.62%, N, 10.04%; Calculated: C, 46.19%, H, 4.57%,N, 9.97%; HPLC purity: 98.6% (R+S isomer)

EXAMPLE 26 Synthesis of1-[2(S)-aminobutyryl]-4-methylindoline-2(R/S)-carboxylic acid(2,2,2-trifluoroethyl)amide trifluoroacetate Ethyl azidoacetate

This compound was prepared from ethyl bromoacetate as described inexample 7.

Ethyl 2-azido-3-(2-methylphenyl)butanoate

Sodium pieces (5.15 g, 240 mmol) were added in portions to ethanol (157ml). The resulting solution was cooled in an ice/acetone bath to −15° C.and then over one hour a mixture of 2-methylbenzaldehyde (7.209 g, 60mmol) and ethyl azidoacetate (30.980 g, 240 mmol) was added at a ratethat maintained the temperature below 10° C. After 3 hours, the solutionwas stored at 5° C. for two days to give pure product as yellowcrystals.

4-Methylindole-2-carboxylic acid ethyl ester

This compound was prepared from ethyl2-azido-3-(2-methylphenyl)butanoate as described in example 7.

4-Methylindoline-2(R/S)-carboxylic acid ethyl ester

This compound was prepared from 4-methylindole-2-carboxylic acid ethylester as described in example 7. The product was purified by columnchromatography on silica gel using 20:1 dichloromethane: diethyl etheras eluent.

1-[N-t-Butoxycarbonyl-2(S)-aminobutyryl]-4-methylindoline-2(R/S)-carboxylicacid methyl ester

This compound was prepared from 4-methylindoline-2(R/S)-carboxylic acidmethyl ester as described in example 7.

1-[N -t-Butoxycarbonyl-2(S)-aminobutyryl]-4-methylindoline-2(R/S)carboxylic acid

This compound was prepared from1-[N-t-butoxycarbonyl-2(S)-aminobutyryl]-4-methylindoline-2(R/S)-carboxylicacid methyl ester as described in example 7.

1-[N-t-Butoxycarbonyl-2(S)-aminobutyryl]-4-methylindoline-2(R/S)-carboxylicacid (2,2,2-trifluoroethyl)amide

This compound was prepared from1-[N-t-butoxycarbonyl-2(S)-aminobutyryl]4-methylindoline-2(R/S)-carboxylicacid as described in example 7.

1-[2(S)-Aminobutyryl]-4-methylindoline-2(R/S)-carboxylic acid(2,2,2-trifluoroethyl)amide trifluoroacetate

This compound was prepared from1-[N-t-butoxycarbonyl-2(S)-aminobutyryl]4-methylindoline-2(R/S)-carboxylicacid (2,2,2-trifluoroethyl)amide as described in example 7.

mp 109-122° C.; Elemental analysis: C₁₆H₂₀F₃N₃O₂; 1.3(CF₃CO₂H); Found:C, 45.54%, H, 4.03%, N, 8.83%; Calculated: C, 45.45% H, 4.37%, N, 8.55%;HPLC purity: 98.6% (R+S isomer).

EXAMPLE 27 Synthesis of1-[2(S)-aminobutyryl]-4,5-dimethoxyindoline-2(R/S)-carboxylic acid(2,2,2-trifluoroethyl)amide trifluoroacetate Methyl2-azido-3-(2,3-dimethoxyphenyl)propenoate

This compound was prepared from 2,3-dimethoxybenzaldehyde as describedin example 7.

4,5-Dimethoxyindole-2-carboxylic acid methyl ester

This compound was prepared from methyl2-azido-3-(2,3-dimethoxyphenyl)propenoate as described in example 26.The product was purified by column chromatography on silica gel using4:1 petroleum spirit:ethyl acetate as eluent.

4,5-Dimethoxyindoline-2(R/S)-carboxylic acid methyl ester

This compound was prepared from 4,5-dimethoxyindole-2-carboxylic acidmethyl ester as described in example 22. The product was purified bycolumn chromatography on silica gel using 7:3 petroleum spirit:ethylacetate as eluent.

1-[N-t-Butoxycarbonyl-2(S)-aminobutyryl]-4,5-dimethoxyindoline-2(R/S)-carboxylicacid methyl ester

This compound was prepared from 4,5-dimethoxyindoline-2(R/S)-carboxylicacid methyl ester as described in example 7. The product was purified bycolumn chromatography on silica gel using 3:1 petroleum spirit:ethylacetate as eluent.

1-[N-t-Butoxycarbonyl-2(S)-aminobutyryl]-4,5-dimethoxyindoline-2(R/S)carboxylic acid

This compound was prepared from1-[N-t-butoxycarbonyl-2(S)-aminobutyryl]-4,5-dimethoxyindoline-2(R/S)-carboxylicacid methyl ester as described in example 7.

1-[N-t-Butoxycarbonyl-2(S)-aminobutyryl]-4,5-dimethoxyindoline-2(R/S)-carboxylicacid (2,2,2-trifluoroethyl )amide

This compound was prepared from1-[N-t-butoxycarbonyl-2(S)-aminobutyryl]-4,5-dimethoxyindoline-2(R/S)-carboxylicacid as described in example 7.

1-[2(S)-Aminobutyryl-]4,5-dimethoxyindoline-2(R/S)-carboxylic acid(2,2,2-trifluoroethyl)amide trifluoroacetate

This compound was prepared from1-[N-t-butoxycarbonyl-2(S)-aminobutyryl]-4,5-dimethoxyindoline-2(R/S)-carboxylicacid (2,2,2-trifluoroethyl)amide as described in example 7.

mp 79-87° C.; Elemental analysis: C₁₇H₂₂F₃N₃O₄; 1.7(CF₃CO₂H); Found: C,42.43%, H, 4.27%, N, 6.91%; Calculated: C, 42.01%, H, 4.10%, N, 7.20%;HPLC purity: 100% (R+S isomer).

EXAMPLE 28 Synthesis of1-[2(S)-aminobutyryl]-4,6-methylenedioxyindoline-2(R/S)-carboxylic acid(2,2,2-trifluoroethyl)amide trifluoroacetate 2,3-Methylenedioxybenzaldehyde

To a mechanically stirred degassed mixture of 2,3-dihydroxy benzaldehyde(7.80 g, 56 mmol) and cesium carbonate (16.20 g, 84 mmol) inacetonitrile (110 ml) was added bromochloromethane (5.46 g, 84 mmol) andthe resulting suspention was heated to reflux. After 5 hours thereaction was cooled to room temperature and filtered through celite withethyl acetate washings. The filtrate was concentrated and directlychromatographed on silica gel using 9:1 hexane:ethyl acetate as eluent.

Methyl 2-azido-3-(2,3-methylenedioxyphenyl)propenoate

A solution of 2,3-methylenedioxy benzaldehyde (15.76 g, 104 mmol) andmethylazidoacetate (48.38 g, 419 mmol) in methanol was cooled to −15° C.using an ice/acetone bath. The resulting solution was then treated overone hour with sodium methoxide (96 ml) at a rate that maintained thetemperature below −10° C. After 3 hours, the solution was stored at 5°C. for two days to give crystalline material which was filtered off andwashed with hexane.

4,5-Methylenedioxyindole-2-carboxylic acid methyl ester

This compound was prepared from methyl2-azido-3-(2,3-methylenedioxyphenyl)propenoate as described in example26. The product was purified by column chromatography on silica gelusing 8:1 petroleum spirit:ethyl acetate as eluent.

4,5-Methylenedioxyindoline-2(R/S)-carboxylic acid

This compound was prepared from 4,5-methylenedioxyindole-2-carboxylicacid methyl ester as described in example 1. However this time 10equivalence of magnesium turnings were used instead of 2-3 eq. ofmagnesium turnings. The product was purified by column chromatography onsilica gel using 7:3 petroleum spirit:ethyl acetate as eluent.

1-[N-t-Butoxycarbonyl-2(S)-aminobutyryl]-4,5-methylenedioxyindoline-2(R/S)-carboxylic acidmethyl ester

This compound was prepared from4,5-methylenedioxyindoline-2(R/S)-carboxylic acid methyl ester asdescribed in example 1. The product was purified by columnchromatography on silica gel using 10:1 petroleum spirit:ethyl acetateas eluent.

1-[N-t-Butoxycarbonyl-2(S)-aminobutyryl]-4,5-methylenedioxyindoline-2(R/S)-carboxylicacid

This compound was prepared from1-[N-t-butoxycarbonyl-2(S)-aminobutyryl]-4,5-methylenedioxyindoline-2(R/S)-carboxylic acid methyl ester as described in example 1.The product was purified by column chromatography on silica gel using5:1 dichloromethane:methanol as eluent.

1-[N-t-Butoxycarbonyl-2(S)-aminobutyryl]-4,5-methylenedioxyindoline-2(R/S)-carboxylicacid (2,2,2-trifluoroethyl)amide

This compound was prepared from1-[N-t-butoxycarbonyl-2(S)-aminobutyryl]-4,5-methylenedioxyindoline-2(R/S)-carboxylic acid as described in example 7. The productwas purified by column chromatography on silica gel using 3:1 petroleumspirit:ethyl acetate as eluent.

1-[2(S)-Aminobutyryl]-4,5-methylenedioxyindoline-2(R/S)-carboxylic acid(2,2,2-trifluoroethyl)amide trifluoroacetate

This compound was prepared from1-[N-t-butoxycarbonyl-2(S)-aminobutyryl]-4,5-methylenedioxyindoline-2(R/S)-carboxylic acid (2,2,2-trifluoroethyl)amide as describedin example 7.

mp 89-98° C.; Elemental analysis: C₁₆H₁₈F₃N₃O₄; 1.5(CF₃CO₂H); Found: C,43.95%, H, 4.13%, N, 7.40%; Calculated: C, 43.68%, H, 4.21%, N, 7.04%;HPLC purity: 100% (47.9%, 52.4%) (R+S isomer).

EXAMPLE 29 Synthesis of1-[2(S)-aminobutyryl]-5-ethynylindoline-2(R/S)-carboxylic acid(2,2,2-trifluoroethyl)amide trifluoroacetate hydrate1-[N-t-Butoxycarbonyl-2(S)-aminobutyryl]-5-benzyloxyindoline-2(R/S)-carboxylicacid (2,2,2-trifluoroethyl)amide

This compound was prepared from1-[N-t-butoxycarbonyl-2(S)-aminobutyryl]-5-benzyloxyindoline-2(R/S)-carboxylicacid (from example 6) as described in example 1. The product waspurified by column chromatography on silica gel using 3:1 petroleumspirit:ethyl acetate as eluent.

1-[N-t-Butoxycarbonyl-2(S)-aminobutyryl]-5-hydroxyindoline-2(R/S)-carboxylicacid (2,2,2-trifluoroethyl)amide

1-[N-t-butoxycarbonyl-2(S)-aminobutyryl]-5-benzyloxyindoline-2(R/S)-carboxylicacid (2,2,2-trifluoroethyl)amide (1.27 g, 5.39 mmol) in ethyl acetate(28 ml) was hydrogenated under an atmosphere of hydrogen in theprescence of palladium on activated carbon at room temperature for 24hours. The catalyst was filtered through celite with ethyl acetatewashing. The filtrate was concentrated and directly chromatographed onsilica gel using 2:3 petroleum spirit:ethyl acetate as eluent.

1-[N-t-Butoxycarbonyl-2(S)-aminobutyryl]-5-trifluoromethyl sulfonatoindoline-2(R/S)-carboxylic acid (2,2,2-trifluoroethyl)amide

1-[N-t-butoxycarbonyl-2(S)-aminobutyryl]-5-hydroxyindoline-2(R/S)-carboxylicacid (2,2,2-trifluoroethyl)amide (0.87 g, 1.95 mmol) in pyridine (6 ml)was cooled to 0° C. using an ice bath under an atmosphere of nitrogen.Triflic anhydride (0.66 g, 2.34 mmol) was added. After one hour thesolution was stored at 5° C. for a day. The reaction mixture wasconcentrated and the residue purified by column chromatography on silicagel using 5:1 petroleum spirit:ethyl acetate as eluent.

1-[N-t-Butoxycarbonyl-2(S)-aminobutyryl]-5-(trimethylsilyl)ethynylindoline-2(R/S)-carboxylic acid (2,2,2-trifluoroethyl)amide

A mixture of 1-[N-t-butoxycarbonyl-2(S)-aminobutyryl]-5-trifluoromethylsulfonateindoline-2(R/S)-carboxylic acid (2,2,2-trifluoroethyl)amide(0.83 g, 1.43 mmol), trimethylsilyl acetylene (0.24 ml, 2.15 mmol),triethylamine (2.26 ml) and dichlorobis(triphenylphosphine)palladium (70mg, 0.10 mmol) in dimethylformamide (11 ml) was stirred at 90° C. for 4hours under an atmosphere of nitrogen. The reaction mixture was thencooled to room temperature, diluted with brine and extracted with ethylacetate. The organic layers were dried over anhydrous magnesium sulphateand evaporated in vacuo. The crude residue was purified by columnchromatography on silica gel using 4:1 petroleum spirit:ethyl acetate aseluent.

1-[N-t-Butoxycarbonyl-2(S)-aminobutyryl]-5-ethynylindoline-2(R/S)-carboxylicacid (2,2,2-trifluoroethyl)amide

To the solution of1-[N-t-butoxycarbonyl-2(S)-aminobutyryl]-5-(trimethylsilyl)ethynylindoline-2(R/S)-carboxylicacid (2,2,2-trifluoroethyl)amide (0.43 g, 0.81 mmol) in anhydrousmethanol (7ml), potassium carbonate (0.02 g) was added under anatmosphere of nitrogen and stirred at room temperature for severalhours. The solvent was evaporated in vacuo.

1-[2(S)-Aminobutyryl]-5-ethynylindoline-2(R/S)-carboxylic acid(2,2,2-trifluoroethyl)amide trifluoroacetate hydrate

This compound was prepared from1-[N-t-butoxycarbonyl-2(S)-aminobutyryl]-5-ethynylindoline-2(R/S)-carboxylicacid (2,2,2-trifluoroethyl)amide as described in example 7.

mp 140-149° C.; Elemental analysis: C₁₇H₁₈F₃N₃O₃; 2.3(CF₃CO₂H):1.0(H₂O);Found: C, 40.87%, H, 3.75%, N, 6.46%; Calculated: C, 40.93%, H, 3.55%,N, 6.63%; HPLC purity: 100% (45.3%, 54.6%) (R+S isomer).

Measurement of the Inhibition of Tripeptidyl Peptidase II (TPP II)

The inhibition of TPP II was measured using the procedure described inWO 96/35805.

The potency of the compounds of the invention was evaluated by measuringthe activity of membrane TPP II. The degree of inhibition by thecompounds of the invention is expressed as the dissociation constant(Ki), calculated from the concentration needed to provide 50%inhibition, and from the K_(m) of the substrate (23 μM).

Membranes of rat cerebral cortex were obtained by centrifugation(200,000×g min) of a homogenate in 10 volumes of a 50 mM potassiumphosphate buffer, pH 7.4.

The centrifugation pellet was carefully washed and taken up in a buffercontaining 10% glycerol and 0.1% Brij 35 to obtain a concentration of 25mg protein/ml.

After 25 minutes of preincubation, incubation is carried out in 0.1 mlof a buffer containing 0.1% Brij 35, 100 mM bestatin, 25 μg of membraneprotein and 50 μm of substrate Ala-Ala-Phe-Amc (AAF-Amc). Liberation of7-amino4-methylcoumarin (Amc) is evaluated by fluorimetry.

Table 1 shows the inhibition data obtained for the compounds of Examples1 to 10.

TABLE 1 Inhibition of AAF-Amc Hydrolysis by Cerebral Membranes. Compoundof Example Ki (nM) 1 0.40 2 1.7 3 15 4 3 5 1.2 6 2.8 7 0.56 8 0.36 9 0.710 1.1

Table 2 shows comparative data between the following comparativecompounds known in the art for their inhibiting activity on TPP II andsome compounds of the invention:

C.C.1: 1-(2(S)-aminobutyryl)-5-chloroindoline-2(S)-carboxylic acidn-butylamide

C.C.2: 1-(2(S)-aminobutyryl)-indoline-2(S)-carboxylic acid n-butylamide(named Butabindide);

C.C.3: 1-(2(S)-aminobutyryl)-indoline-2(S)carboxylic acid ethylamide

C.C.4: 1-(2(S)-aminobutyryl)-5-hydroxyindoline-2(R/S)-carboxylic acidn-butylamide

C.C.5: 1-(2(S)-aminobutyryl)-5-methoxyindoline-2(R/S)-carboxylic acidn-butylamide

TABLE 2 Inhibition of AAF-Amc Hydrolysis by Cerebral MembranesComparative Compound of the compound Ki (nM) invention Ki (nM) C.C.1 2.5ex. 1 0.4 C.C.2 7 ex. 4 3 C.C.3 12 ex. 5 1.2 C.C.4 6.6 ex. 6 2.8 C.C.5 8ex. 9 0.7

What is claimed is:
 1. A compound of the following formula I:

wherein: each R¹ may be the same or different, and is selected from thegroup consisting of halogen, OH; C₁-C₆ alkyl optionally substituted byone or more radicals selected from the group consisting of halogen andOH; (C₁-C₆) alkenyl optionally substituted by one or more radicalsselected from the group consisting of halogen and OH; (C₁-C₆) alkynyl,optionally substituted by one or more radicals selected from the groupconsisting of halogen and OH, X(C₁-C₆)alkyl, wherein X is S, 0 or OCO,and the alkyl is optionally substituted by one or more radicals selectedfrom the group consisting of halogen and OH; SO₂(C₁-C₆)alkyl, optionallysubstituted by at least one halogen, YSO₃H, YSO₂(C₁-C₆)alkyl, wherein Yis O or NH and the alkyl is optionally substituted by at least onehalogen, a diradical —X¹—(C₁-C₂)alkylene-X¹— wherein X¹ is O or S; and abenzene ring fused to the indoline ring; n is from 0 to 4; R² is CH₂R⁴,wherein R⁴ is C₁-C₆ alkyl substituted by one or more radicals selectedfrom the group consisting of halogen and OH; (CH₂)_(p)Z(CH₂)_(q)CH₃,wherein Z is O or S, p is from 0 to 5 and q is from 0 to 5, providedthat p+q is from 0 to 5; (C₂-C₆) unsaturated alkyl; or (C₃-C₆)cycloalkyl; or R² is (C₁-C₆)alkyl or O(C₁-C₆)alkyl, each optionallysubstituted by at least one halogen; R³ is H; (C₁-C₆)alkyl optionallysubstituted by at least one halogen; (CH₂)_(p)ZR⁵ wherein p is from 1 to3, Z is O or S and R⁵ is H or (C₁-C₃)alkyl; benzyl; or apharmaceutically acceptable acid addition salt thereof; provided that:when R¹ is a halogen atom; a O—(C₁-C₄)alkyl; OH or (C1-C4)alkyl group;R² is CH₂R⁴ wherein R⁴ is (CH₂)₂SCH₃, —(CH₂)₂OH or cyclohexyl; or R² isa (C₁-C₆)alkyl group; then R³ is neither a hydrogen atom nor a(C₁-C₄)alkyl group.
 2. A compound according to claim 1, wherein: each R¹may be the same or different, and is selected from the group consistingof halogen, OH, (C₁-C₆)alkyl, optionally substituted by one or moreradicals selected from the group consisting of halogen and OH,X(C₁-C₆)alkyl, wherein X is S, O or OCO, optionally substituted by oneor more radicals selected from the group consisting of halogen and OH,SO₂(C₁-C₆)alkyl, optionally substituted by at least one halogen, YSO₃H,and YSO₂(C₁-C₆)alkyl, wherein Y is O or NH optionally substituted by atleast one halogen; n is from 0 to 4; R² is CH₂R⁴, wherein R⁴ is(C₁-C₆)alkyl substituted by one or more radicals selected from the groupconsisting of halogen and OH; (CH₂)_(p)Z(CH₂)_(q)CH₃, wherein Z is O, S,p is from 0 to 5 and q is from 0 to 5, provided that p+q is from 0 to 5;(C₂-C₆) unsaturated alkyl; or (C₃-C₆) cycloalkyl; or R² is (C₁-C₆)alkylor O(C₁-C₆)alkyl, each optionally substituted by at least one halogen;R³ is H; (C₁-C₆)alkyl.
 3. A compound according to claim 1 wherein R³ ishydrogen, methyl or ethyl.
 4. A compound according to claim 1, whereinR³ is a (C₁-C₆)alkyl optionally substituted by at least one halogen;(CH₂)_(p)ZR⁵ where p, Z and R⁵ are as defined in claim 1; or benzyl. 5.A compound according to claim 4, wherein R³ is —(CH₂)₂SCH₃.
 6. Acompound according to claim 1, wherein R² is CH₂R⁴, R⁴ being(C₁-C₆)alkyl substituted by at least one halogen; (CH₂)_(p)Z(CH₂)_(q)CH₃wherein Z is O, p and q are as defined in claim 1; (C₂-C₆) unsaturatedalkyl; or R² is 0 (C₁-C₆)alkyl optionally substituted by at least onehalogen.
 7. A compound according to claim 1, wherein R² is CH₂R⁴, R⁴ isselected from the group consisting of CH₂OCH₃, CH₂SCH₃, SCH₃, CH(OH)CH₃,C═CH₂, C≡CH and cyclopropyl; or R² is NHCH₃.
 8. A compound according toclaim 1, wherein R² contains at least one halogen atom.
 9. A compoundaccording to claim 8, wherein R² is CH₂R⁴ with R⁴ selected from thegroup consisting of CHF₂, CF₃, CF₂CF₃, CH₂F, and CH₂Cl.
 10. A compoundaccording to claim 1, wherein n is
 0. 11. A compound according to claim1, wherein n is not 0 and R¹ is (C₁-C₆)alkyl substituted by one or moreradicals selected from the group consisting of halogen and OH;X(C₁-C₆)alkyl wherein X is S or OCO, optionally substituted by one ormore radicals selected from the group consisting of halogen and OH;O(C₁-C₆)alkyl substituted by one or more radicals selected from thegroup consisting of halogen and OH; SO₂(C₁-C₆)alkyl, optionallysubstituted by at least one halogen; or YSO₃H; YSO₂(C₁-C₆)alkyl whereinY is O or NH optionally substituted by at least one halogen.
 12. Acompound according to claim 1, wherein R¹ is CH₃, OCH₃, Cl, F, OH, OCF₃,OSO₃H, OSO₂CH₃, OCOCH₃, OSO₂CF₃, SO₂CH₃, SCH₃, NHSO₂CH₃ or CF₃.
 13. Acompound according to claim 1, wherein n is not 0 and R¹ is(C₁-C₆)alkenyl or (C₁-C₆)alkynyl.
 14. A compound according to claim 13,wherein R¹ is —C═CH—.
 15. A compound according to claim 1, wherein n is1 and R¹ is a diradical —X¹—(C₁-C₂)alkylene-X¹— where X¹ is as definedin claim
 1. 16. A compound according to claim 15, wherein R¹ is —OCH₂O—.17. A compound according to claim 1, wherein n is 1 and R¹ is a benzenering fused to an indoline ring.
 18. A compound according to claim 1,wherein n is 1 or
 2. 19. A compound according to claim 1, which isselected from the group consisting of:1-(2(S)-aminobutyryl)-5-chloroindoline-2(S)-carboxylic acid(2,2,2-trifluoroethyl)amide,1-(2(S)-aminobutyryl)-5-chloroindoline-2(S)-carboxylic acid2-chloroethylamide, 1-(2(S)-aminobutyryl)-indoline-2(S) carboxylic acid(2-methylthioethyl)amide, 1-(2(S)-aminobutyryl)-indoline-2(S)-carboxylicacid N-(cyclopropylmethyl)amide,1-(2(S)-aminobutyryl)-indoline-2(S)-carboxylic acid(2,2,2-trifluoroethyl)amide,1-(2(S)-aminobutyryl)-5-hydroxyindoline-2(R/S)-carboxylic acid(2,2,2-trifluoroethyl)amide,1-(2(S)-aminobutyryl)-4-chloroindoline-2(R/S)-carboxylic acid(2,2,2-trifluoroethyl)amide,1-(2(S)-aminobutyryl)-4-fluoroindoline-2(R/S)-carboxylic acid(2,2,2-trifluoroethyl)amide,1-(2(S)-aminobutyryl)-5-methoxyindoline-2(R/S)-carboxylic acid(2,2,2-trifluoroethyl)amide,1-(2(S)-aminobutyryl)-5-trifluoromethoxyindoline-2(R/S)-carboxylic acid(2,2,2-trifluoroethyl)amide and pharmaceutically acceptable saltsthereof.
 20. A compound according to claim 1, which is selected from thegroup consisting of:1-[2-(S)-aminobutyryl]-4,5-dichloro-indoline-2-(R/S)-carboxylic acidbutyl amide trifluoroacetate,1-[2-(S)-aminobutyryl]-4,5-dichloro-indoline-2-(S)-carboxylic acid2,2,2-trifluoroethylamide trifluoroacetate,1-[2-(S)-aminobutyryl]-5,6-dichloro-indoline-2-(S)-carboxylic acid2,2,2-trifluoroethylamide trifluoroacetate,1-[2-(S)-aminobutyryl]-benz-[e]-indoline-2-(S)-carboxylic acid2,2,2-trifluoroethylamide trifluoroacetate,1-[2-(S)-aminobutyryl]-5-O-sulfato-indoline-2(R/S)-carboxylic acid butylamide trifluoroacetate,1-[2-(S)-aminobutyryl]-benz-[e]-indoline-2-(S)-carboxylic acid butylamide trifluoroacetate,1-[2-(S)-aminobutyryl]-4,5-dichloro-indoline-2-(R/S)-carboxylic acid2,2,2-trifluoroethylamide trifluoroacetate,1-[2-(S)-aminobutyryl]-5-O-sulfato-indoline-2(R/S)-carboxylic acidtrifluoroethylamide trifluoroacetate,1-[2-(S)-aminobutyryl]-benz[f]-indoline-2-(S/R)-carboxylic acid2,2,2-trifluoroethylamide trifluoroacetate hemi hydrate,1-[2-(S)-phenylalanyl)-5-Cl-indoline 2(R/S)-carboxylic acid2,2,2-trifluoroethylamide trifluoroacetate,1-[2(S)-aminobutyryl]-4-methoxyindoline-2(S)-carboxylic acid(2,2,2-trifluoroethyl)amide trifluoroacetate,1-[2-glycyl]-5-chloroindoline-2(R/S)-carboxylic acid(2,2,2-trifluoroethyl)amide trifluoroacetate,1-[2(S)-alanyl]-5-chloroindoline-2(R/S)-carboxylic acid(2,2,2-trifluoroethyl)amide hemitrifluoroacetate,1-[2(S)-norvalyl]-5-chloroindoline-2(R/S)-carboxylic acid(2,2,2-trifluoroethyl)amide trifluoroacetate,1-[2(S)-methionyl]-5-chloroindoline-2(R/S)-carboxylic acid(2,2,2-trifluoroethyl)amide trifluoroacetate,1-[2(S)-aminobutyryl]-4-methylindoline-2(R/S)-carboxylic acid(2,2,2-trifluoroethyl)amide trifluoroacetate,1-[2(S)-aminobutyryl]-4,5-dimethoxyindoline-2(R/S)-carboxylic acid(2,2,2-trifluoroethyl)amide trifluoroacetate,1-[2(S)-aminobutyryl]-4,5-methylenedioxyindoline-2(R/S)-carboxylic acid(2,2,2-trifluoroethyl)amide trifluoroacetate,1-[2(S)-aminobutyryl]-5-ethynylindoline-2(R/S)-carboxylic acid(2,2,2-trifluoroethyl)amide trifluoroacetate hydrate andpharmaceutically acceptable salts thereof.
 21. A process for preparing acompound of formula I according to claim 1, which process comprises a)reacting a compound of the following formula II:

with an optionally protected amino acid R³CH(NHR¹⁰)COOH (III), where n,R¹ and R³ are as defined in claim 1 and R¹⁰ is H or a protecting group,to obtain a compound of the following formula IV:

wherein R¹ is methoxy, b) optionally hydrolysing the ester (IV) to thecorresponding acid, c) reacting the acid or ester (IV) with an amine offormula R²NH₂, and d) optionally removing the protecting group R¹⁰, andoptionally converting the product thus obtained into a salt.
 22. Aprocess for preparing the compound of formula I according to claim 1,which process comprises e) reacting a compound of formula V:

with an optionally protected amino acid of the formula (III)R³CH(NHR¹⁰)COOH, wherein, n, R¹, R², R³ and R¹⁰ are as defined in claim1, to obtain a compound of the following formula (IV):

wherein R¹ is NHR², optionally removing the protecting group R¹⁰, andoptionally converting the product thus obtained into a salt.
 23. Apharmaceutical composition acting as an inhibitor of theCCK-inactivating peptidase tripeptidyl peptidase (TPP II), whichcomprises a therapeutically effective amount of a compound according toclaim 1, and a pharmaceutically acceptable carrier or diluent.
 24. Apharmaceutical composition according to claim 23, further comprising acompound effective in the treatment of obesity, a compound acting on theamylin receptor or a compound that increases the levels ofnoradrenaline, dopamine or serotonin in the brain.
 25. A pharmaceuticalcomposition according to claim 23, comprising an effective dosage of acompound according to claim 1 suitable for an administration of 0.001 to10 mg per kg body weight per day.
 26. A cosmetic composition comprisinga compound according to claim 1 and a physiologically acceptable carrieror diluent.
 27. Method for the treatment of diseases requiring theinhibition of CCK-inactivating peptidase tripeptidyl peptidase (TPP II)comprising the administration of a therapeutically effective amount of acompound of formula I according to claim 1 to a human in need thereof.28. Method for the treatment of an over-eating disorder comprising theadministration of a therapeutically effective amount of a compound offormula I according to claim 1 to a human in need thereof.
 29. Methodfor the treatment of obesity comprising the administration of atherapeutically effective amount of a compound of formula I according toclaim 1 to a human in need thereof.
 30. Method according to claim 29comprising the combined administration of a compound of formula I and ofa compound effective in the treatment of obesity.
 31. Method accordingto claim 29 comprising the combined administration of a compound offormula I and of a compound effective in the treatment of obesityselected from the group consisting of an adrenergic β₃-receptor agonist,a histamine H₃-receptor antagonist, a neuropeptide Y receptor(NPY-5)antagonist, a compound acting on an amylin receptor and acompound that increases the levels of noradrenaline, dopamine orserotonin in a brain.
 32. Method according to claim 31 comprising thecombined administration of a compound of formula I and of a compoundselected from the group consisting of dexfenfluramine, sibutramine andfluoxetine.
 33. Method for the treatment of psychotic syndromes andassociated psychiatric disorders comprising the administration of atherapeutically effective amount of a compound of formula I according toclaim 1 to a human in need thereof.
 34. Method for slimming comprisingthe administration of a therapeutically effective amount of a compoundof formula I according to claim 1 to a human in need thereof.
 35. Apharmaceutical composition according to claim 24 wherein the compoundeffective in the treatment of obesity is selected from the groupconsisting of an adrenergic β₃-receptor agonist, a histamine H₃-receptorantagonist, and a neuropeptide Y receptor (NPY-5) antagonist.
 36. Apharmaceutical composition according to claim 24 wherein the compoundthat increases the levels noradrenaline, dopamine or serotonin in thebrain is selected from consisting of dexfenfluramine, sibutramine andfluoxetine.